First power bill for my 6 GH/s rig

[JayCoin]

$300 extra on my power bill and $600 worth of bitcoins mined. Time to quit my day job.

[1715653300]

1715653300

[1715653300]

1715653300

[1715653300]

1715653300

[trouserless]

$300 extra on my power bill and $600 worth of bitcoins mined. Time to quit my day job.

What do you pay for power? What is your card/rig setup?

[Transisto]

What is you day job ?

What car do you drive ?

[rjk]

$300 a month. Wheee. I'll keep my day job, thanks

[evoorhees]

$300 a month. Wheee. I'll keep my day job, thanks

Clearly your day job is not in finance... else you'd see that OP is making a 100% operating profit and it's just a matter of scale before quitting a day job would be a reality.

[rjk]

$300 a month. Wheee. I'll keep my day job, thanks

Clearly your day job is not in finance... else you'd see that OP is making a 100% operating profit and it's just a matter of scale before quitting a day job would be a reality.

GPUs don't scale linearly unless you live somewhere where it is cold year round for free cooling, and you have a lot of space.

[Littleshop]

$300 a month. Wheee. I'll keep my day job, thanks

Clearly your day job is not in finance... else you'd see that OP is making a 100% operating profit and it's just a matter of scale before quitting a day job would be a reality.

GPUs don't scale linearly unless you live somewhere where it is cold year round for free cooling, and you have a lot of space.

True. 

One rig = 100% profit.

Ten and you need to pay for cooling, and maybe space as well. You will see failures.  Sure, there are some people who have a place to put in 10 GPU's and not pay for cooling.... but most can not. 

[Beaflag VonRathburg]

I'd also be interested to know what your rigs contain and how much you pay for power. I'm waiting for my first bill to come in as well.

[Global BTC]

What was your initial investment?

[Tullphan]

I would also like to know what you pay for power.

[pla]

GPUs don't scale linearly unless you live somewhere where it is cold year round for free cooling, and you have a lot of space.

Sure they do - Just vent them outside.  One 20" box window fan will move the heat of a LOT of GPUs outside (unless you live somewhere with an outside temperature already over 110F).

DAMN but I wish I lived somewhere other than one of the highest $-per-KW states right about now.

[rjk]

GPUs don't scale linearly unless you live somewhere where it is cold year round for free cooling, and you have a lot of space.

Sure they do - Just vent them outside.  One 20" box window fan will move the heat of a LOT of GPUs outside (unless you live somewhere with an outside temperature already over 110F).

DAMN but I wish I lived somewhere other than one of the highest $-per-KW states right about now.

Where does the incoming air come from? From your air conditioner, right? Or, if no A/C, then it comes from the outside - which could easily be 90-110 degrees Fahrenheit. QED.

[phorensic]

GPUs don't scale linearly unless you live somewhere where it is cold year round for free cooling, and you have a lot of space.

Sure they do - Just vent them outside.  One 20" box window fan will move the heat of a LOT of GPUs outside (unless you live somewhere with an outside temperature already over 110F).

DAMN but I wish I lived somewhere other than one of the highest $-per-KW states right about now.

Where does the incoming air come from? From your air conditioner, right? Or, if no A/C, then it comes from the outside - which could easily be 90-110 degrees Fahrenheit. QED.

I was about to post the same thing, lol.  I don't care how much air you can exhaust out your window from your mining room, it comes *IN* from somewhere.  And in most locations the ambient air temp outside is going to get hot enough to kill the whole idea of just using a fan.

[sveetsnelda]

Where does the incoming air come from? From your air conditioner, right? Or, if no A/C, then it comes from the outside - which could easily be 90-110 degrees Fahrenheit. QED.

I was about to post the same thing, lol.  I don't care how much air you can exhaust out your window from your mining room, it comes *IN* from somewhere.  And in most locations the ambient air temp outside is going to get hot enough to kill the whole idea of just using a fan.

Exactly.  This is why internal combustion engines in our cars stop working in the summer time.   ...no wait...   

You guys realize that 110 degrees Fahrenheit is "only" 43 Celsius, right?  That's still over 30 degrees lower than the temperature my GPUs run at.  With enough airflow, the heat will certainly still be removed so long as the heat isn't recirculated through the cards.

[phorensic]

I'm glad you don't design data centers for a living.  You would kill a lot of hardware with your lack of knowledge.

[pla]

Where does the incoming air come from? From your air conditioner, right? Or, if no A/C, then it comes from the outside - which could easily be 90-110 degrees Fahrenheit. QED.

I was about to post the same thing, lol.  I don't care how much air you can exhaust out your window from your mining room, it comes *IN* from somewhere.  And in most locations the ambient air temp outside is going to get hot enough to kill the whole idea of just using a fan.

Where does it come from?  No, not your air conditioner - You open... wait for it... Another window.
Hot enough to kill the whole idea?  Seriously?  Do you folks live in Death Valley?

I'm glad you don't design data centers for a living.  You would kill a lot of hardware with your lack of knowledge.

I don't design datacenters for a living, but Microsoft has a few guys you might need to set straight:
http://blogs.msdn.com/b/the_power_of_software/archive/2008/09/19/intense-computing-or-in-tents-computing.aspx
Let me know how they respond to your concerns.   

[phorensic]

That article was more theory than proven practice.  They only had 5 servers...in a tent, using way less power than something loaded with GPU's.  Lets try to scale that up and see what happens.

There are *very* few places on earth where you can get away with cooling a dense DC with just ambient outside air.  Trust me, Google and Facebook have looked very hard and written great articles about it.  In the end they are forced to put DC's in places where the local temps get too hot, within the course of a year, to work with just outside air.  We aren't talking about running a bunch of mining rigs just in the dead of winter.  And when I say too hot it's not like I'm talking 135F.  They end up using some form of energy input into the system to get the temps down.  You would be surprised what Facebook can do by misting water into their fresh/recirc air.  But that still takes power to pump!  Not to mention the cost of the water!

And yes, it just so happens that I have had to design data centers in my career.  Including power and cooling for them!

[rjk]

The key to the problem is the temperature delta. Sure ambient might "only" be 43 degrees C, but is that low enough to keep the server within tolerance after adding all the heat from the CPUs, RAM, SCSI cards, etc? Usually not.

[sveetsnelda]

I'm glad you don't design data centers for a living.  You would kill a lot of hardware with your lack of knowledge.

Oh yes.  Complete lack of knowledge.    I've made national news for my "lack of knowledge" regarding hardware.  If you took thermodynamics or fluid dynamics classes, you obviously flunked.

Funny you should mention it...  I actually do.    I work for a fairly large enterprise.  Commercial data centers generally have other restrictions imposed on them or have other design concerns to work around.  I certainly have a bit more freedom with my home rigs.

My 45 Ghash of equipment is currently putting out about 21.5KW of heat and they are crammed together in a more heat dense fashion than most data centers would ever allow (Amazon's EC2 possibly being an exception).  I'm currently cooling everything with a standalone small household fan for each rig and 2 window fans.  It gets into the high 90's and occasionally the low 100's here in the summer (desert climate).  I used a small evap cooler last year during the summer because my current layout ends up recirculating a little of the air from one rig to the next.  With the right building design and powerful fans, I wouldn't need an evap cooler at all.  The fans on my reference cards are never running above 60 percent (right now, most of them are in the low 30's because the inlet air temp is still so cool).

In two weeks, I'll be migrating all of my rigs to a dedicated building in the back yard.  In the summer, I won't need evap cooling if I want to run the fans a little high because I'll be exhausting ALL of the hot air and routing it properly.  Can't wait to "kill a lot of hardware"!

[sveetsnelda]

The key to the problem is the temperature delta. Sure ambient might "only" be 43 degrees C, but is that low enough to keep the server within tolerance after adding all the heat from the CPUs, RAM, SCSI cards, etc? Usually not.

Of course it is.  ...just not when you cram everything into a 1U case and flow hot air from one component to the next.  Again, if this statement were true, we'd all have to shut down our cars in the summer.

[DeathAndTaxes]

Again, if this statement were true, we'd all have to shut down our cars in the summer.

Can you please stop using the broken card analogy.  You may be right but your car analogy annoys the every loving shit out of me. 

Car operating temp is ~200F (90C).   The higher the heat differential the easier it is to move heat.  So car @ 200F and ambient at 100F = 100F difference.  You can accomplish same amount of cooling with a lot less airflow than trying to keep a GPU @ 60C/140F with ambient @ 100F = 40F difference.

Also car engines are watercooled for a reason.  It moves the heat into a radiator with massive surface area. 

So in summary
* the hotter the device is relative to ambient = easier to cool
* the larger the surface area is relative to ambient = easier to cool
* the higher the airflow = easier to cool

Just because a car can be kept "cool" (when cool = 100F over ambient temp) doesn't mean it applies to GPUs.

So please stop with the car analogy nonsense.  It doesn't help your case.

[sveetsnelda]

The analogy is far from "broken".

The car analogy wasn't meant to be overly technical or precise.  Judging by your posts, you obviously understand the basics of thermaldynamics.  My arguement was with someone who apparently does not.  If my argument was with someone who did, no broad analogy would have been needed.

That being said, everything in your post just explained exactly why my internal combustion engine analogy makes perfect sense.  He said something along the lines of "Video cards are hot.  When the air temperature warms up, enough heat can't possibly be removed".  My response was "Yeah?  Engines are hot too and we keep them temperature controlled in the summer just fine."

Yep.  Most modern automobile engines are water cooled for many reasons...  the biggest of which being that the engine is crammed into a compartment for aestetics and protection.  Noise and emissions are up there too.  I don't plan on putting my GPUs in a case and rolling them down the freeway anytime soon though.  I also don't burn hydrocarbons in my GPUs, so I don't need to worry about NOX levels.    Another reason they're water cooled is because it's easier to regulate the temperature to tighter tolerances than air cooling (using a thermostat).  If an internal combustion engine runs too cold, performance/efficiency suffers heavily.  There are plenty of modern air cooled internal combustion engines out there as well though.  I could give a pretty good dissertation on the subject because I study/build/repair/modify gasoline engines.  It's not very relevant to the discussion though.

Just because a car can be kept "cool" (when cool = 100F over ambient temp) doesn't mean it applies to GPUs.

So please stop with the car analogy nonsense.  It doesn't help your case.

Combustion engines produce substantial heat.  GPUs produce substantial heat.  Both require heat removal to prevent failure and both have very large temperature deltas compared to ambient temperature air.  Yeah, I see they are both completely unrelated.

[DeathAndTaxes]

Combustion engines produce substantial heat.  GPUs produce substantial heat.  Both require heat removal to prevent failure and both have very large temperature deltas compared to ambient temperature air.  Yeah, I see they are both completely unrelated.

A long winded nothing and you missed the only point.

Car's cooling system can effectively dump the heatload because a car can operate at 200F.  That is 100F OVER ambient under worst case scenario.   If a car's cooling system had to keep car's internal temp at <140F then a car (as built today) would be insufficient to operate when outside temp is 100F+.  If a car could operate effectively at 300F it would need a SMALLER cooling system (relative to heat load) to keep temps <300F when ambient is 100F.

Car = 200F operating temp = 100F Delta T to ambient*
GPU = <140F operating temp = <40F Delta T to ambient*

On edit:
* further and likely unecessary clarificaiton because sveetsnelda is either an idiot or a troll ...

Code:

ambient in this case would be 100F input air time. The input air time he indicates is sufficient to cool his farm.  Yes it may also be cooler parts of the year but your idiotic trolling aside it wasn't your claim that you could cool the GPU with outside air when airtime if 0F your claim was you could cool them when outside airtime was 100F.

The point of the 100F vs 40F is that given 100F AMBIENT AIR TEMP it is much easier to cool something (easier as in surface area and airflow requires) when you only need to keep it at 100F OVER AMBIENT.  It is much harder (as in amount of surface area and airflow required) to keep operating temps at only 40F OVER AMBIENT.  Yes sveetsnelda I know what over ambient means.  Maybe you forgot but your claims was you could cool GPU with 100F input air.  Not sure why it is sooooooooooooooo complicated but if your are cooling something and the T-In is 100F then that is your ambient temperature.  You can't cool anything below ambient without phase change so that becomes the baseline.   A perfect cooling system could keep card temp at Ambient.  Such a system would be massive though so the Delta over ambient determines the amount of cooling (in terms of surface area, and airflow) necessary.  40 Delta over ambient is harder to achieve than a Delta of 100F over ambient for the same heat load.

The fact that a car can operate (at 100F over ambient) doesn't prove anything.  A nuclear reactor can continue to operate at 600F over ambient that doesn't mean a water cooled rig that keeps a GPU at 600F over ambient will be effective.  Why do reactors run at 600F?  Because the cooling system can be smaller/cheaper/more efficient than if it needed to operate at 500F, or 200F (car), or 140F (GPU).

40F Delta T is not much to work with.  The smaller the Delta T the more volume necessary to transfer the same amount of thermal energy and the same surface area.  If you can keep an entire farm stable 24/7 with 100F input air temps well you are better than most.  My guess is you 100F temps are with low humidity? Still your stupid car analogy is just that ... stupid.

[Sannyasi]

I'm glad you don't design data centers for a living.  You would kill a lot of hardware with your lack of knowledge.

lawl

but more on topic = Invest slowly and build your farm over time. Huge bitcoin mining investments usually fail (Going off past posts I've found here). Slowly working your way up helps you learn alot of things you'd never consider otherwise, plus if you work up over time it's much easier to deal with anything that might go wrong.

[sveetsnelda]

 

A GPU can not operate at 100F over ambient.

In the winter, my inlet air is around 0F (or lower).  My GPUs are regulated by fans to around 160F (71C).  I guess mine are magical because that's a 160 degree difference and I have a few cards that are 3 years old and still doing GPGPU computation 24/7.  I'll just assume that you are trying to say something different here or you are setting some specific value for "ambient" in your head...

So using car as an analogy is as dubious as using a pressurized water reactor as an analogy.

You are completely overcomplicating the argument.  The original statement/arguement was that a GPU cannot be cooled with 90-100F air.  I said that the statement/arguement was wrong and silly because a GPU most certainly can if you provide it with a constant supply of fresh air.  You're arguing my side and apparently not realizing it.

GPU also don't work well at 345C either.

I never said or implied that they do.

If a car needed to operate at no more than 40F over ambient then cooling system would need to be radically changed.

Agreed.  At only 40F over ambient, the fuel would never combust.    The cooling system could just be stripped out entirely.     Jokes aside, I'll assume you're saying "coolant temperature at only 40F over ambient" because you were apparently quoting coolant temperature before when you used the 200F figure.  If you wanted a vehicle's coolant to run at only 40F above ambient on the freeway, just remove the thermostat.    No radical redesign necessary.  Don't say that I didn't warn you that it'll only burn 5 percent of its fuel though. 

GPU need to operate at no more than 140F (worst case scenario that is only 40F over ambient) thus car is a dubious analogy.

Err...  if that's the case, then everyone who fires up Crysis 2, Furmark, OCCT, or Furmark without manually controlling their fan speed will trash their GPUs.  Most of the recent ATI cards will happily run at 70-75C and will even stay stable to 80C.  The clock throttle on most BIOSes are set to around 90C (194F).  "No more than 140F" is pretty low.  Not only is it low, but it's lower than the manufacturer sets the auto-fan profile to.  They are certainly designed to run hotter.  Longevity is a different argument altogether.

Are you sure that you're not confusing the term "over ambient"?  This applies to water coolant temperature, but doesn't apply to air cooling (or air cooling a radiator) in the way that you are stating...  Engineers don't design an air cooled device (like a video card) to run at a certain temperature over ambient.  They design what temperature/temperature range the device should run at and then specify the minimum/maximum ambient temperatures that will allow it to stay within the set thermal threshold.

[DeathAndTaxes]

I'm done.  You indicated you can aircool at 100F ambient temps.   So yes ambient temp would = 100F.  40F OVER AMBIENT would be (here let me help you)

100F + 40F = 140F.

Keeping the GPU temp below 140F would require a cooling system that can achieve 40 deg F OVER AMBIENT when the Ambient temp is 100F.

It doesn't really matter what happens on the coldest day does it troll?  Since despite 5 posts you don't seem to grasp that I will take it you intent is just to troll and let you troll on.

[chiropteran]

Car = 200F operating temp = 100F Delta T to ambient.
GPU = <140F operating temp = <40F Delta T to ambient.

There is a problem with your well thought out argument.  Most GPU run fine up to 95C.  VRMs, which can sometimes be the limiting factor, function up to 120C.  The delta difference just isn't as big as you think it is.


Now, a video card will almost certainly last longer at 60C than it will at 90C, this is true.  But to make any accurate measure of value you need to look at the cost of the card over it's lifespan in each case and determine if the increased GPU lifespan is worth spending additional funds on cooling.  Then there are other variables, for example you might be better off and end up with lower temperatures AND lower overall cost by using a water-cooling system with outdoor air vs an indoor air cooling system with AC.

[sveetsnelda]

*shrug*.  Whatever.  You're missing the point.  An analogy is meant to be just that -- an analogy...  not a perfect comparison of every aspect.  It's done for simplicity in order to get someone to connect with one aspect of the analogy.  By your logic, the only valid analogy to cooling a GPU is cooling a GPU.

Yes, I'm obviously just a troll.    Look at my post history.  I'm an obvious troublemaker.  I try to correct someone's misinformation and that's trolling?  You correct misinformation in many threads, so you must be a troll too.    Your posts are generally informative and logical.  These have been derogatory and angry like you have a grudge.  Yes, feel free to ignore me if your responses are going to continue to be that way.  I'll go back to my 45Ghash of "magical" GPUs and continue to scale it with my air cooled "sorcery".

[DeathAndTaxes]

There is a problem with your well thought out argument.  Most GPU run fine up to 95C.  VRMs, which can sometimes be the limiting factor, function up to 120C.  The delta difference just isn't as big as you think it is.

A GPU running at 95C core and 120C VRM isn't going to last long.  A farm with dozens of GPU at 95C core and 120C VRM is going to be a complete nightmare to manage.  You will end up making less than minimum wage dealing with the nonstop crashes, hardlocks, equipment failure, and downtime.   I don't know any serious miner which runs the cards at 95C for 24/7 operation.  I shoot for 70C operating temps.  At 80C cgminer is dropping their clocks to keep temps in line.  VRM are pushed hard when mining.  They tend to run 20C+ hotter than core temps.  None of my cards have seen 95C core and hopefully never will.

[k9quaint]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

[rjk]

I would love to have 0 degree air to cool my rigs year round, but I don't have that luxury. I need to find something that will work for me in hot humid weather.

[RDarke]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Hmmm. How do people drive VW Beetles(real ones) in the summer then?

[phorensic]

DeathAndTaxes, I would like to see sveetsnelda cool a large, dense mining cluster with 100F intake air.  All he needs is enough airflow, right? lol.  Have fun with the power and noise required to move that much air.  This is where water steps in and becomes way more efficient.  You still have to use forced airflow to dump the heat in the end, but it is NOTHING like designing a large scale air only system.  I'm glad he designs data centers for a living also.  He should tell Facebook they did it all wrong with their latest DC.

Edit:  I missed where he said on the last page in this thread where he lives in a dry climate that gets to 100F and he had to use evap to control the temps. lol

[k9quaint]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Hmmm. How do people drive VW Beetles(real ones) in the summer then?

Overheating on hills or in stopped traffic in hot weather is a common problem with the air cooled bugs & vanagons. They changed the engine to be watercooled to address this. There were also aftermarket oil cooling bolt ons to address this problem. Those engines were designed during an era when stop & go in 100 degree heat was not the usual situation (as it became in Los Angeles).

[cablepair]

i just want to comment here as someone who actually ran a decent size mining operation all summer long last year

unless you live in the arctic circle or some damn place your going to need a powerful and high quality air conditioner to cool the immediate space around your rigs - there's just no way around it

i had about 6ghash over the summer and i had a brand new Frigidaire 12.5k btu ac and on real hot days it struggled to keep up and the only area it was cooling was my mining room - and this is upstate ny, if you live in arizona or something similar your going to need some real cooling power

[RDarke]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Hmmm. How do people drive VW Beetles(real ones) in the summer then?

Overheating on hills or in stopped traffic in hot weather is a common problem with the air cooled bugs & vanagons. They changed the engine to be watercooled to address this. There were also aftermarket oil cooling bolt ons to address this problem. Those engines were designed during an era when stop & go in 100 degree heat was not the usual situation (as it became in Los Angeles).

If you say so. I've never had problems in well over 100 degree heat and left idling with it or my 911. I'd be more worried about my Fieros overheating than either of those. But then most people couldn't find the engine let alone take care of it.

[k9quaint]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Hmmm. How do people drive VW Beetles(real ones) in the summer then?

Overheating on hills or in stopped traffic in hot weather is a common problem with the air cooled bugs & vanagons. They changed the engine to be watercooled to address this. There were also aftermarket oil cooling bolt ons to address this problem. Those engines were designed during an era when stop & go in 100 degree heat was not the usual situation (as it became in Los Angeles).

If you say so. I've never had problems in well over 100 degree heat and left idling with it or my 911. I'd be more worried about my Fieros overheating than either of those. But then most people couldn't find the engine let alone take care of it.

The problem isn't idling, the problem is sustained high output at low speeds. Put 4 people in a Vanagon and then drive up a hill in 100 degree heat. Hook a trailer to your 911 and haul a couple thousand pounds uphill in 100 degree heat, see what happens when you do lots of work and are not going 60 MPH. FYI they switched the 911 to be water cooled in 1998.

Finally, those engines are technically oil-cooled and have radiators to dump the waste heat from the oil. Since they are actually liquid cooled, they are not really appropriate to this analogy.

[RDarke]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Hmmm. How do people drive VW Beetles(real ones) in the summer then?

Overheating on hills or in stopped traffic in hot weather is a common problem with the air cooled bugs & vanagons. They changed the engine to be watercooled to address this. There were also aftermarket oil cooling bolt ons to address this problem. Those engines were designed during an era when stop & go in 100 degree heat was not the usual situation (as it became in Los Angeles).

If you say so. I've never had problems in well over 100 degree heat and left idling with it or my 911. I'd be more worried about my Fieros overheating than either of those. But then most people couldn't find the engine let alone take care of it.

The problem isn't idling, the problem is sustained high output at low speeds. Put 4 people in a Vanagon and then drive up a hill in 100 degree heat. Hook a trailer to your 911 and haul a couple thousand pounds uphill in 100 degree heat, see what happens when you do lots of work and are not going 60 MPH. FYI they switched the 911 to be water cooled in 1998.

Finally, those engines are technically oil-cooled and have radiators to dump the waste heat from the oil. Since they are actually liquid cooled, they are not really appropriate to this analogy.

Actually I have towed with the 911. It was only a small lawn trailer but it was loaded with parts so it was probably about 2k lbs. Not a problem except for the car being squirrely and not being able to get out of it's own way.

My Jeep, Blazer and Fieros all have oil coolers too. Doesn't make them oil cooled.

Try harder or we've derailed this thread enough.

[RandyFolds]

 

A GPU can not operate at 100F over ambient.

In the winter, my inlet air is around 0F (or lower).  My GPUs are regulated by fans to around 160F (71C).  I guess mine are magical because that's a 160 degree difference and I have a few cards that are 3 years old and still doing GPGPU computation 24/7.  I'll just assume that you are trying to say something different here or you are setting some specific value for "ambient" in your head...

So using car as an analogy is as dubious as using a pressurized water reactor as an analogy.

You are completely overcomplicating the argument.  The original statement/arguement was that a GPU cannot be cooled with 90-100F air.  I said that the statement/arguement was wrong and silly because a GPU most certainly can if you provide it with a constant supply of fresh air.  You're arguing my side and apparently not realizing it.

GPU also don't work well at 345C either.

I never said or implied that they do.

If a car needed to operate at no more than 40F over ambient then cooling system would need to be radically changed.

Agreed.  At only 40F over ambient, the fuel would never combust.    The cooling system could just be stripped out entirely.     Jokes aside, I'll assume you're saying "coolant temperature at only 40F over ambient" because you were apparently quoting coolant temperature before when you used the 200F figure.  If you wanted a vehicle's coolant to run at only 40F above ambient on the freeway, just remove the thermostat.    No radical redesign necessary.  Don't say that I didn't warn you that it'll only burn 5 percent of its fuel though. 

GPU need to operate at no more than 140F (worst case scenario that is only 40F over ambient) thus car is a dubious analogy.

Err...  if that's the case, then everyone who fires up Crysis 2, Furmark, OCCT, or Furmark without manually controlling their fan speed will trash their GPUs.  Most of the recent ATI cards will happily run at 70-75C and will even stay stable to 80C.  The clock throttle on most BIOSes are set to around 90C (194F).  "No more than 140F" is pretty low.  Not only is it low, but it's lower than the manufacturer sets the auto-fan profile to.  They are certainly designed to run hotter.  Longevity is a different argument altogether.

Are you sure that you're not confusing the term "over ambient"?  This applies to water coolant temperature, but doesn't apply to air cooling (or air cooling a radiator) in the way that you are stating...  Engineers don't design an air cooled device (like a video card) to run at a certain temperature over ambient.  They design what temperature/temperature range the device should run at and then specify the minimum/maximum ambient temperatures that will allow it to stay within the set thermal threshold.

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

[pla]

That article was more theory than proven practice.  They only had 5 servers...in a tent, using way less power than something loaded with GPU's.  Lets try to scale that up and see what happens.
[...]
And yes, it just so happens that I have had to design data centers in my career.  Including power and cooling for them!

Then, as a data center designer, could you kindly explain to me what, exactly, fails to "scale up" when using outside ambient air to cool?  Just how high of a server density do you need before "outside" experiences a significant increase in temperature?

Trust me, Google and Facebook have looked very hard and written great articles about it.

Yes, they have.  And you have apparently read them, because you specifically mention their impressive improvements on the boring ol' "swamp cooler".  So no doubt, you know all about Facebook's newest DC in Lulea, where they expect to need less than two weeks of supplemental active cooling per year.

Now compare the form factor and uptime demands of a hardcore miner against a Facebook datacenter - And try to tell me with a straight face that you don't see just the teensiest difference between a room full of mid-tower PCs loaded with GPUs that can go down for an hour or two in mid-afternoon on the hottest days of the year with no real harm done, vs row after row after freakin' row of 24core x 42U racks with a contractually guaranteed six-nines uptime?

[DeathAndTaxes]

An hour or two of downtime a day?  Fuck I am mad when I have an hour or two of downtime a month.

You are aware Lulea is in Sweden right?  No 100F summers w/ 90% humidity in Sweden last time I checked.  In related news I doubt the datacenter at the south pole research base needs a lot of phase change cooling either.

[cablepair]

An hour or two of downtime a day?  Fuck I am mad when I have an hour or two of downtime a month.

You are aware Lulea is in Sweden right?  No 100F summers w/ 90% humidity in Sweden last time I checked.  In related news I doubt the datacenter at the south pole research base needs a lot of phase change cooling either.

+1

you cant compare gaming to mining, playing even the most demanding game is nothing in comparison to overclocking and pushing your fan and gpu hashing away 24/7

these gpus are designed to game not to mine, you need to keep that in mind. Sure you can take a brand new card and beat the shit out of it in high temps and it will last awhile

try to buy a used card from someone on the marketplace part of the forum, something that served a good year mining 24/7 that thing is not going to last a month in 90degree heat and humidity without proper cooling

[sveetsnelda]

Edit:  I missed where he said on the last page in this thread where he lives in a dry climate that gets to 100F and he had to use evap to control the temps. lol

Cool story "breh"...  except you filled in the part about the temps with your words instead of mine...  and the rigs are in a damn bedroom with window fans.  I could have easily shut the water pump off and continued to run the fan alone and the rigs would have been fine.  In fact, there were a few times where the girlfriend forgot to turn it on when she left for work (I shut it off at night and just used window fans).  The NOISE is what I was especially trying to manage since these are in my home.

Are you people

A - Jealous
B - Assholes to everyone you meet in "real life" too
or
C - Just completely ignorant?

I'm dumbfounded that I came in to a thread to simply correct misinformation with a decent attitude and I'm getting shit on by multiple people.  There's a difference between a friendly objective argument/debate of facts and immediately treating someone as if they are inferior/stupid.  I'm far from it.  It's like being bullied for being a nerd in high school or something...

[trentzb]

I save these threads that start out "First power bill for my 6 GH/s rig" and end up about volkswagen vans, spark plugs, thermodynamic theory and oil coolers...to read when I have had too much to drink.

Based on the cost/performance I would guess somewhere in the $0.10 per kW/h that the OP is paying. Anyone else have a guess if the OP doesn't share? Or did I miss the actual numbers?

[phorensic]

That article was more theory than proven practice.  They only had 5 servers...in a tent, using way less power than something loaded with GPU's.  Lets try to scale that up and see what happens.
[...]
And yes, it just so happens that I have had to design data centers in my career.  Including power and cooling for them!

Then, as a data center designer, could you kindly explain to me what, exactly, fails to "scale up" when using outside ambient air to cool?  Just how high of a server density do you need before "outside" experiences a significant increase in temperature?

Trust me, Google and Facebook have looked very hard and written great articles about it.

Yes, they have.  And you have apparently read them, because you specifically mention their impressive improvements on the boring ol' "swamp cooler".  So no doubt, you know all about Facebook's newest DC in Lulea, where they expect to need less than two weeks of supplemental active cooling per year.

Now compare the form factor and uptime demands of a hardcore miner against a Facebook datacenter - And try to tell me with a straight face that you don't see just the teensiest difference between a room full of mid-tower PCs loaded with GPUs that can go down for an hour or two in mid-afternoon on the hottest days of the year with no real harm done, vs row after row after freakin' row of 24core x 42U racks with a contractually guaranteed six-nines uptime?

The difference I see is that we are packing much more power draw (read: heat generation) into a smaller space than what has been pointed out in this thread.  Now you are comparing to 24 cores in a single chassis, but lets be more realistic and reference the MSDN tent article again.  Modern servers are awesome with how much CPU they can cram into a 2u/4u form factor, or whatever servers you have, but they are also extremely efficient on power use nowadays.  Also, the load on a typical server is very random and usually nowhere near 100%, unless you are running simulations or rendering Pixar movies or whatever.  We load to 100% 24/7 with fire breathing GPU's packed right next to each other.  What runs stable in that little tent they used cannot be compared to racks of GPU's the way we do it.  Pulling air in a window on one side of a house and exhausting it through a window on the other side where you mining operation is just cannot be done after a certain level of power draw/heat generation.

[phorensic]

Are you people

A - Jealous
B - Assholes to everyone you meet in "real life" too
or
C - Just completely ignorant?

B - Because when it comes to topics like this, I have way more experience than anyone I meet in a typical day.  Now when I talk to people who have big titles in the enterprise computing world, *that's* when I start to listen instead of school.

[sveetsnelda]

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

It's a delta-t of 65.2F.  I don't run my air-cooled GPUs at 60C.  I'd like the fans to last more than a few months and I don't need the GPUs to keep running for decades.

I'm not doing your homework.  Judging by your previous posts, you'd turn mine into a conspiracy theory.  If you knew enough about the subject to understand the calculations one would post, you'd realize that a temperature differential of 65F isn't really THAT difficult to work with when you have a decent supply of fresh air.  I'm not showing you my birth certificate either.

[sveetsnelda]

A car with an air cooled engine would stop working during the summer if it became stuck in stop and go traffic.

Analogy fails.

Every small engine manufacturer and motorcycle manufacturer laughs in your general direction.

[sveetsnelda]

B - Because when it comes to topics like this, I have way more experience than anyone I meet in a typical day.  Now when I talk to people who have big titles in the enterprise computing world, *that's* when I start to listen instead of school.

I can relate to that.  However, this means that you should be a skeptic when you first meet someone and then transition to asshole when it's a guarantee that the person is a complete moron or unwilling to learn/listen.

Also, someone with a big title in the enterprise world definitely shouldn't be enough to "start listening".  I've worked with some serious morons who have "big titles" that would look great on paper, but any enthusiast/hobbyist would school him/her.

[RandyFolds]

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

It's a delta-t of 65.2F.  I don't run my air-cooled GPUs at 60C.  I'd like the fans to last more than a few months and I don't need the GPUs to keep running for decades.

I'm not doing your homework.  Judging by your previous posts, you'd turn mine into a conspiracy theory.  If you knew enough about the subject to understand the calculations one would post, you'd realize that a temperature differential of 65F isn't really THAT difficult to work with when you have a decent supply of fresh air.  I'm not showing you my birth certificate either.

I grow dope and fish for a living, bro. I have no idea what volume of cross-flow you would need to dissipate 21.5kW of heat with 100F ambient temperatures, nor how to calculate it.

I can say that I have dealt with ~25kw of indoor lighting, and it took a six-ton compressor working it's ass off and fans that no one on earth would call 'window fans' even when the intake temps were in the sixties(F).

[pla]

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

A typical window fan moves 2000-2500CFM.

The average bedroom measures a mere 86ft^2, or roughly 600ft^3 - Meaning a $20 window box fan will completely remove the air from the room every 15 seconds.

A typical woodstove puts out 3.4KWH/Kg, or somewhere around 10-15KW.  Mine does closer to 15.

And put bluntly, if I put a box fan in the room with my stove, with a window opposite it open to allow air in - I would freeze to death in the winter.  And I don't speculate on this, I've done it when I "burned in" my stove.  Two years ago, in late autumn, at 60F outside, I fired that sucker up to a good 700F with a fan blowing out the nearest window to out-gas the enamel... And it didn't make a damned bit of difference in the ambient temperature of my house.  Standing directly between the stove and the window, you could feel perhaps a +5F difference.

So, if your box will run, at ambient, at full load without cooking itself, for a mere 15-30 seconds - Really, the outdoor temperature will suffice to cool it.  A crappy Lasko window fan (and two open windows in an area you can conveniently close off from the rest of the house) will do the job juuuuust fine.



phorensic... Look, I don't think we substantially disagree on this, and might even respect each other IRL.  But 15-20KW of misused gaming rigs still doesn't come anywhere near datacenter loads, even if they may have a higher spatial density.  If you really want to extend the point to "miners" pulling half a megawatt, I'll concede the point.

[phorensic]

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

It's a delta-t of 65.2F.  I don't run my air-cooled GPUs at 60C.  I'd like the fans to last more than a few months and I don't need the GPUs to keep running for decades.

I'm not doing your homework.  Judging by your previous posts, you'd turn mine into a conspiracy theory.  If you knew enough about the subject to understand the calculations one would post, you'd realize that a temperature differential of 65F isn't really THAT difficult to work with when you have a decent supply of fresh air.  I'm not showing you my birth certificate either.

I grow dope and fish for a living, bro. I have no idea what volume of cross-flow you would need to dissipate 21.5kW of heat with 100F ambient temperatures, nor how to calculate it.

I can say that I have dealt with ~25kw of indoor lighting, and it took a six-ton compressor working it's ass off and fans that no one on earth would call 'window fans' even when the intake temps were in the sixties(F).

Cannabis and fish together or separately?  I'm trying to get my aquaponics setup going right now, but it will just grow leafy greens and maybe peppers.  Hard to find edible fish to grow around here too, so I just have some hobby style fish.

[trouserless]

I grow dope and fish for a living, bro. I have no idea what volume of cross-flow you would need to dissipate 21.5kW of heat with 100F ambient temperatures, nor how to calculate it.

+1 I laughed so hard I spat a bit of my beer up...

[PulsedMedia]

lawl

but more on topic = Invest slowly and build your farm over time. Huge bitcoin mining investments usually fail (Going off past posts I've found here). Slowly working your way up helps you learn alot of things you'd never consider otherwise, plus if you work up over time it's much easier to deal with anything that might go wrong.

+1.
I setup my original cluster ALL wrong, result was barely 1.28Mhash/W, 2xFailed 5850, failed mobo, room like a sauna.

Now i'm looking towards to achieving over 4Mhash/W with newer hardware!

[DeathAndTaxes]

pla why do you keep talking about winter time?

How about turn on that stove when outside temp is 110F and try to keep indoor temps down with a window box fan.

[chiropteran]

This thread is just so LOL.

Looking back at the post that started it...

You guys realize that 110 degrees Fahrenheit is "only" 43 Celsius, right?  That's still over 30 degrees lower than the temperature my GPUs run at.  With enough airflow, the heat will certainly still be removed so long as the heat isn't recirculated through the cards.

Note the bold part, which is key.  All you trolls coming in and talking about how you can't do it because 25kw produces so much heat blah blah blah are just looking like fools. 

The point was that with enough airflow you could cool a mining rig with 110F outside air.   Is anyone going to actually dispute this, or is this thread just going to be trolling followed by trolling? Most of the made up situations that are just straw-men arguments which don't follow the original statement.

[DeathAndTaxes]

The "enough airflow" as indicated was a pair of box fans.  So yes with enough airflow you could cool GPU with furnace air at 130F but you certainly aren't with a box fan.

I don't think you know what the word "trolling" means.

[rjk]

Hey guys! I know how to keep my miners within a proper temperature at 100+ degrees Fahrenheit in the summer! I just need one of these per rig:



No actually fuck that, do you have any idea how many watts those things pull? And how loud? Damn.

[cablepair]

Wood From my Basement = FREE
Various Pipes, Valves, & Pressure Gauges (Stolen from my neighbors basement) = FREE
Hamster Wheel = $2.99 (used salvation army)
Hamster = $4.99 (Pet Shop)

Currently its getting about 1 Mhash per bag of Hamster Food
but im looking into ways to make it more efficient
(rats, mice, racoons etc)

if you guys are so smart than tell me how I can keep my latest rig cool!

at first I was giving the hamster water and then I switched to gatorade

now when I stick a anal thermometer up his ass hes registering about 50c which was still cooler than my 5970 but id like to see it a little cooler

[sveetsnelda]

There's that "objective discussion" again.    They don't want to learn, they just want their wrong opinion to be right.

[rjk]

There's that "objective discussion" again.    They don't want to learn, they just want their wrong opinion to be right.

Teach me, Master. Tell me the way to cool a rig with 100 degree summer air, WITHOUT making more noise than the fans being at 50%, and without pulling a significant number of extraneous watts.

[sveetsnelda]

Oh, for sure.  I love educating others and sharing knowledge while they treat me like shit.  Let me get right on that.   

[rjk]

Oh, for sure.  I love educating others and sharing knowledge while they treat me like shit.  Let me get right on that.   

Pretty sure you aren't going to be able to come up with a way, but if you can I will certainly retract any statement that I made earlier that is invalid or incorrect.

[chiropteran]

There's that "objective discussion" again.    They don't want to learn, they just want their wrong opinion to be right.

Teach me, Master. Tell me the way to cool a rig with 100 degree summer air, WITHOUT making more noise than the fans being at 50%, and without pulling a significant number of extraneous watts.

I don't think anyone claimed the fans would be silent.  Nobody mentioned the amount of "extraneous watts".

It was simply a question of can you do it, yes or no.  The answer is yes, you can.  Can rjk add some new restrictions or special situations to create an artificial situation where air cooling may not work, sure.  But you are answering a different question at that point, one which is irrelevant to the original thread.

It looks like you realize you have lost the original argument, so you are moving the goalposts.

[rjk]

There's that "objective discussion" again.    They don't want to learn, they just want their wrong opinion to be right.

Teach me, Master. Tell me the way to cool a rig with 100 degree summer air, WITHOUT making more noise than the fans being at 50%, and without pulling a significant number of extraneous watts.

I don't think anyone claimed the fans would be silent.  Nobody mentioned the amount of "extraneous watts".

It was simply a question of can you do it, yes or no.  The answer is yes, you can.  Can rjk add some new restrictions or special situations to create an artificial situation where air cooling may not work, sure.  But you are answering a different question at that point, one which is irrelevant to the original thread.

It looks like you realize you have lost the original argument, so you are moving the goalposts.

Does anyone know the reason that most datacenters specify that ambient air be between 68 and 75 degrees F? Anyone? Don't disappoint me now.

If I wish to cool my rigs to an acceptable temperature with a low outside ambient temp, I use an open window and no additional fans, or perhaps a small fan to direct the air to an appropriate location. If I wish to do the same in the summer, I need massive amounts of air flowing, which requires noise and power. And even then, the cards are not going to remain within a tolerance that I wish to see.

You can cool your rigs with ambient air at close to 90 degrees and low GPU fan speed - OK, what is the core temperature? 75, 80, 85 degrees C?

[PulsedMedia]

Hey guys! I know how to keep my miners within a proper temperature at 100+ degrees Fahrenheit in the summer! I just need one of these per rig:



No actually fuck that, do you have any idea how many watts those things pull? And how loud? Damn.

Depends on model, but i actually have one with over 2kW rating >

[PulsedMedia]

Teach me, Master. Tell me the way to cool a rig with 100 degree summer air, WITHOUT making more noise than the fans being at 50%, and without pulling a significant number of extraneous watts.

Honestly thinking about that, you can get "semi-free" airflow by utilizing the heat ... Yes, utilizing the heat generated
So assume you have a tent, say yurt / pyramid shaped.
The shape of "roof" is like a funnel, constantly accelerating the air flow, on top you have say a 500x500mm hole with that sized fan, but very low wattage, say 15-30W
Below you have an open air opening.
Because heat tends to go upwards, and BIG fans tend to be more efficient moving air around, you are going to get a decent air flow amount ...

Just saying ...

[DeathAndTaxes]

Wasn't the claim that one could cool 20KW of heat load with a pair of window fans in 100F ambient temps?

Funny how the topic has changed to custom building design, 3 square foot holes in the roof, 2000 watt blowers, datacenters in sweden, "anything can be cooled with enough airflow", how houses get cold when you open the window in winter, and other distractions.

What happened to 20KW heat load, pair of window fans and 100F ambient temps?  

[PulsedMedia]

What happened to 20KW of heat load, pair of window fans and 100F ambient temps? 

Who knows .... Wait what load? XD

I thought that was achieved with evaporative cooling?

[phorensic]

Wasn't the claim that one could cool 20KW of heat load with a pair of window fans in 100F ambient temps?

Funny how the topic has changed to custom building design, 3 square foot holes in the roof, 2000 watt blowers, datacenters in sweden, "anything can be cooled with enough airflow", how houses get cold when you open the window in winter, and other distractions.

What happened to 20KW heat load, pair of window fans and 100F ambient temps?  

Best summary of what happened, IMO.

[chiropteran]

Does anyone know the reason that most datacenters specify that ambient air be between 68 and 75 degrees F? Anyone? Don't disappoint me now.

This isn't a data-center.  The beauty of outdoor cooling is that you don't need the ridiculous density of a datacenter.  You can spread things out, you don't need to stuff 20 video cards into a single tower.  Also, given this is just a hobby or personal business for most of us, we are not restricted by customer contractual demands.  Reliability isn't nearly as important or critical.

If I wish to cool my rigs to an acceptable temperature with a low outside ambient temp, I use an open window and no additional fans, or perhaps a small fan to direct the air to an appropriate location. If I wish to do the same in the summer, I need massive amounts of air flowing, which requires noise and power. And even then, the cards are not going to remain within a tolerance that I wish to see.

Like I said, moving the goalposts.  You can cool your rigs with outside air, even in the summer.  Massive amounts of air flowing?  Whatever.  It's all relative.  If that "massive" airflow is cheaper than running the AC 24/7, it's a net gain.  Noise?  Power?  Absoklute power is irrelevant, what matters is the relative power.  If it's less power to cool via blowing air than it is to run an AC unit, the power usage is a gain, not a negative. "A tolerance that I wish to see", lovely.  So it's not even about provable facts anymore, if you decide the numbers aren't good enough you get to win the argument for free?  Nice try, but no.  If the cards work reliably enough than who cares what rfk thinks is the correct temperature.  Your wishes are not important in this discussion.

You can cool your rigs with ambient air at close to 90 degrees and low GPU fan speed -

Is that a small spark of intelligence?  Are you finally starting to understand how heating and cooling works?  If it's possible to cool down to 60C at 90F, how much harder do you think it is to cool to 80C at 110F?

OK, what is the core temperature? 75, 80, 85 degrees C?

Who cares?  He said it could be done, he didn't specify any particular temperature other than the general assumption that the cards were functioning.

Funny how the topic has changed ..."anything can be cooled with enough airflow",

The topic hasn't changed.  That was from the original post that started this discussion.   Nice try though.

[minero1]

bad things happen when you think temperature is heat,

harder to cool anything with lower deltas? of course, but not impossible

swallow it: IT CAN BE DONE.

[rjk]

This isn't a data-center.  The beauty of outdoor cooling is that you don't need the ridiculous density of a datacenter.  You can spread things out, you don't need to stuff 20 video cards into a single tower.  Also, given this is just a hobby or personal business for most of us, we are not restricted by customer contractual demands.  Reliability isn't nearly as important or critical.

You haven't bothered to look at my sig, have you? Density is key and king. Reliability is damn important as well. You might be in it as a hobby, but some folks like to make a business of it. No problem with that.

If I wish to cool my rigs to an acceptable temperature with a low outside ambient temp, I use an open window and no additional fans, or perhaps a small fan to direct the air to an appropriate location. If I wish to do the same in the summer, I need massive amounts of air flowing, which requires noise and power. And even then, the cards are not going to remain within a tolerance that I wish to see.

Like I said, moving the goalposts.  You can cool your rigs with outside air, even in the summer.  Massive amounts of air flowing?  Whatever.  It's all relative.  If that "massive" airflow is cheaper than running the AC 24/7, it's a net gain.  Noise?  Power?  Absoklute power is irrelevant, what matters is the relative power.  If it's less power to cool via blowing air than it is to run an AC unit, the power usage is a gain, not a negative. "A tolerance that I wish to see", lovely.  So it's not even about provable facts anymore, if you decide the numbers aren't good enough you get to win the argument for free?  Nice try, but no.  If the cards work reliably enough than who cares what rfk thinks is the correct temperature.  Your wishes are not important in this discussion.

Do you know what causes a lack of reliability? That's right, heat. 80 C is far too hot to be sufficiently reliable for me, and 60 is just right. "Just working" isn't good enough. Working for years without failure is what is necessary.

You can cool your rigs with ambient air at close to 90 degrees and low GPU fan speed -

Is that a small spark of intelligence?  Are you finally starting to understand how heating and cooling works?  If it's possible to cool down to 60C at 90F, how much harder do you think it is to cool to 80C at 110F?

I have yet to see evidence of actual rigs being cooled to 60C at 90F, and as I said above 80C is completely unacceptable. Since I can't control the temperature in the summer, I may even need to maintain 60C at 110F. Using an existing air conditioning system and making it run continuously is actually more efficient than installing powerful blowers for outside air cooling, since part of the A/C isn't used for this application anyway.

OK, what is the core temperature? 75, 80, 85 degrees C?

Who cares?  He said it could be done, he didn't specify any particular temperature other than the general assumption that the cards were functioning.

I care. I want my cards to last forever. Is that too much to ask?

[RandyFolds]

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

It's a delta-t of 65.2F.  I don't run my air-cooled GPUs at 60C.  I'd like the fans to last more than a few months and I don't need the GPUs to keep running for decades.

I'm not doing your homework.  Judging by your previous posts, you'd turn mine into a conspiracy theory.  If you knew enough about the subject to understand the calculations one would post, you'd realize that a temperature differential of 65F isn't really THAT difficult to work with when you have a decent supply of fresh air.  I'm not showing you my birth certificate either.

I grow dope and fish for a living, bro. I have no idea what volume of cross-flow you would need to dissipate 21.5kW of heat with 100F ambient temperatures, nor how to calculate it.

I can say that I have dealt with ~25kw of indoor lighting, and it took a six-ton compressor working it's ass off and fans that no one on earth would call 'window fans' even when the intake temps were in the sixties(F).

Cannabis and fish together or separately?  I'm trying to get my aquaponics setup going right now, but it will just grow leafy greens and maybe peppers.  Hard to find edible fish to grow around here too, so I just have some hobby style fish.

I have set up a cannabis aquaponics system, but it's too finicky, and requires too much space. Peppers get tall and kinda bulky. You will get a lot more productivity sticking with herbs and greens. Where do you live that you can't get edible fish? Tilapia are pretty easy to snag except in Florida, and they are completely fucking indestructible.



It blows my fucking mind how many idiots are in here arguing that two lasko 20" fans can move enough volume to sufficiently cool a 21.5kw heat source to ~70C with 100F intake air. Chiropteran, you don't seem to understand the claims at hand, nor is there any moving of the goalpost. There is no AC or massive airflow involved. Just two window fans, allegedly.

How about sveets just nuts up and posts one (1) photograph of this 21.5kw farm of his, clearly demonstrating the two window fans?

[chiropteran]

You haven't bothered to look at my sig, have you? Density is key and king. Reliability is damn important as well. You might be in it as a hobby, but some folks like to make a business of it. No problem with that.

Again, you are changing the argument to get the results you want.  Nobody said you could cool a super dense mining cluster in 110F summer heat.  (Nobody said you can't either, but that isn't the point).  If that is your situation, that you consider density the most important aspect even if it means you are throwing away efficiency and value, so be it. However, your personal limitations don't apply to the rest of the world.

Do you know what causes a lack of reliability? That's right, heat. 80 C is far too hot to be sufficiently reliable for me, and 60 is just right. "Just working" isn't good enough. Working for years without failure is what is necessary.

It's really not.  Reliability in mining is largely a cost benefits analysis.  All things equal, a more reliably setup is better, sure.  But all things are not equal.  There is a point where the money you are spending to keep your cards at 60 instead of 70 or 80 is greater than the cost of simply replacing or upgrading failing cards or systems.  I'm not about to do the calculations here, but the point is an arbitrary statement that 60C is best isn't true, unless you can back it up.  The guy who runs cards at 70C but saves $500/month on cooling bills could well come out ahead of you in the long run, even if he has to replace cards more often.

I have yet to see evidence of actual rigs being cooled to 60C at 90F, and as I said above 80C is completely unacceptable. Since I can't control the temperature in the summer, I may even need to maintain 60C at 110F. Using an existing air conditioning system and making it run continuously is actually more efficient than installing powerful blowers for outside air cooling, since part of the A/C isn't used for this application anyway.

I've yet to see any evidence at all from you.  How do I know you aren't actually a monkey?  I seriously doubt that running AC 24/7 uses less electricity than running fans 24/7, especially given the fact that AC system uses fans itself, in addition to all the electricity required for the compressors.  Not going to take your word for it, sorry.  Back it up with some proof.

I care. I want my cards to last forever. Is that too much to ask?

You can have what you want, but the rest of us don't have to play by your rules.  I think it's silly to try to baby your hardware that much, since the constant progress in technology means your cards are going to be slow and obsolete compared to the new things in a few years anyway.  I could care less if my cards fail in 2 years, if it means I can save some money on cooling.  FPGA will probably have completely replaced video card mining by then anyway

[chiropteran]

It blows my fucking mind how many idiots are in here arguing that two lasko 20" fans can move enough volume to sufficiently cool a 21.5kw heat source to ~70C with 100F intake air. Chiropteran, you don't seem to understand the claims at hand, nor is there any moving of the goalpost. There is no AC or massive airflow involved. Just two window fans, allegedly.

How about sveets just nuts up and posts one (1) photograph of this 21.5kw farm of his, clearly demonstrating the two window fans?

Where was this claim?

edit: You mean this post?  https://bitcointalk.org/index.php?topic=67826.msg797258#msg797258

What exactly is "I used a small evap cooler last year during the summer because my current layout ends up recirculating a little of the air from one rig to the next." if not an AC?

What does "standalone small household fan for each rig and 2 window fans" mean to you?  1 fan PER RIG plus window fans isn't "just two window fans".  A window fan could potentially be a lot of different things, you don't have any idea how powerful it is or how much airflow it is producing.

[DeathAndTaxes]

It blows my fucking mind how many idiots are in here arguing that two lasko 20" fans can move enough volume to sufficiently cool a 21.5kw heat source to ~70C with 100F intake air. Chiropteran, you don't seem to understand the claims at hand, nor is there any moving of the goalpost. There is no AC or massive airflow involved. Just two window fans, allegedly.

How about sveets just nuts up and posts one (1) photograph of this 21.5kw farm of his, clearly demonstrating the two window fans?

Where was this claim?

edit: You mean this post?  https://bitcointalk.org/index.php?topic=67826.msg797258#msg797258

What exactly is "I used a small evap cooler last year during the summer because my current layout ends up recirculating a little of the air from one rig to the next." if not an AC?

What does "standalone small household fan for each rig and 2 window fans" mean to you?  1 fan PER RIG plus window fans isn't "just two window fans".  A window fan could potentially be a lot of different things, you don't have any idea how powerful it is or how much airflow it is producing.

Evaporative cooler != AC.

Funny you spent 10 posts defending it and now pages into the thread decide to actually read what you were defending.  You say people are trolling because they are blasting a claim of using 2 window fans to cool ultra high density and saying "that isn't what was claimed" and now you realize you have no idea what was claimed because you didn't read it until just now.  Fans on rigs aren't going to get rid of heat.  As an experiment shut all the doors and windows to a room, crank up 21KW of space heaters and use all the fans you want.  Let me know how you plan to keep the temps below 120F+.

Instead of saying "hey I was an ass I had no idea what was going on" you decide to hold the line on the definition of "window fans".

LOLZ.     Unless he has a 2 meter by 2 meter window one would expect window fan is 20" or less.  Since 9 square feet windows are kind rare one would think that unless someone was trying to hide something would explain that.  i.e. "I can cool it with 2 window fans but then again they are 72" across. j/k "  My any normal persons definition a window fan without clarifiction would be a fan one can fit in a window.  20" maybe 36" across. 

The funny thing is the author of the asinine claim has backed away (not refuting it but certainly not defending it).  You just kept going on and on calling people trolls and saying they were changing the topic, defending something that you hadn't even read.

READ MORE &  RANT LESS.  

[RandyFolds]

It blows my fucking mind how many idiots are in here arguing that two lasko 20" fans can move enough volume to sufficiently cool a 21.5kw heat source to ~70C with 100F intake air. Chiropteran, you don't seem to understand the claims at hand, nor is there any moving of the goalpost. There is no AC or massive airflow involved. Just two window fans, allegedly.

How about sveets just nuts up and posts one (1) photograph of this 21.5kw farm of his, clearly demonstrating the two window fans?

Where was this claim?

edit: You mean this post?  https://bitcointalk.org/index.php?topic=67826.msg797258#msg797258

What exactly is "I used a small evap cooler last year during the summer because my current layout ends up recirculating a little of the air from one rig to the next." if not an AC?

What does "standalone small household fan for each rig and 2 window fans" mean to you?  1 fan PER RIG plus window fans isn't "just two window fans".  A window fan could potentially be a lot of different things, you don't have any idea how powerful it is or how much airflow it is producing.

An evaporative cooler is not a compressor AC. One fan per rig is circulating air within the space, the two window fans provide cross-ventilation. You really can't see a difference between the two?

A window fan is a window fan...a 14" MaxFan would be referred to as a 'window fan' by exactly zero people on this planet, and that's the kind of volume he needs to be moving. As I said above, I have extensive experience dissipating heat from lighting setups. You cannot evacuate 21.5kw of heat in a closed space with two window fans when the intake is at 100F.

[chiropteran]

The funny thing is the author of the asinine claim has backed away (not refuting it but certainly not defending it).  You just kept going on and on calling people trolls and saying they were changing the topic, defending something that you hadn't even read.

READ MORE &  RANT LESS.  

Uh, no.  The claims I have been arguing against and the things I have been "defending" didn't include this post.  This is the first time I've responded to a post talking about that specific situation. 

For all I know the exact situation could be BS, which I why I asked for more details, but it doesn't change the basic point- can you cool a GPU with sufficient airflow in 110F air?  Yes you can.

[DeathAndTaxes]

The funny thing is the author of the asinine claim has backed away (not refuting it but certainly not defending it).  You just kept going on and on calling people trolls and saying they were changing the topic, defending something that you hadn't even read.

READ MORE &  RANT LESS.  

Uh, no.  The claims I have been arguing against and the things I have been "defending" didn't include this post.  This is the first time I've responded to a post talking about that specific situation.  

For all I know the exact situation could be BS, which I why I asked for more details, but it doesn't change the basic point- can you cool a GPU with sufficient airflow in 110F air?  Yes you can.

And?  You jumped in when people claimed the setup described above was implausible.  

It would be like:
Kid #1: I can go to the moon for $8.
Various Kids:  Impossible, not even close, etc
chiropteran:  Hey trolls it is possible.
Various kids: WTF?
(50 worthless post later)
chiropteran:  See I was right.  You can get to the moon given ENOUGH money.

In related news chiropteran most of the time you can (fill in blank) given enough (fill in blank).  It is kinda useless claim.

but it doesn't change the basic point- can you cool a GPU with sufficient airflow in 110F air?

That was never the basic claim in anyones mind except yours.  Generally that is called a strawman. Make up your own weak defense so you can defeat it.

Congrats you winz the interents.

[chiropteran]

Just two window fans, allegedly.

An evaporative cooler is not a compressor AC. One fan per rig is circulating air within the space, the two window fans provide cross-ventilation.

You really can't see a difference between these two statements?  First you come out saying it's just two fans.  Now you say it's just two fans, plus another fan per rig, and an evaporation cooler.  

Slightly different situations, aren't they?  It's hard to take you seriously when you lie or mislead so much before I come in and correct you on the facts.

[chiropteran]

Congrats you winz the interents.

Thanks.  Now go back and read the thread.  I never said the things you say I said.  It was your post that got me into the thread, because you were posting some ridiculous crap about how the temperature delta between 110F and safe GPU operating temperature is too small.  After I destroyed that argument you went on to something else.  

You never said "you can't cool it because the delta is too small and you only have 15 fans plus an evaporation cooler it's not enough".  If you did, perhaps I would have stayed out, I can't argue with that because I don't know all the details.  

I do know there is nothing that makes it impossible to air cool a GPU down to 80C when the ambient temp is 43C.

[RandyFolds]

Just two window fans, allegedly.

An evaporative cooler is not a compressor AC. One fan per rig is circulating air within the space, the two window fans provide cross-ventilation.

You really can't see a difference between these two statements?  First you come out saying it's just two fans.  Now you say it's just two fans, plus another fan per rig, and an evaporation cooler.  

Slightly different situations, aren't they?  It's hard to take you seriously when you lie or mislead so much before I come in and correct you on the facts.

No, I cannot see the difference. Moving air within a confined space does not dissipate heat. Cross ventilation, however, does. See, those fans on each rig...they are a local phenomena, and the two window fans driving the cross-flow are the only things significantly affecting the dissipation of heat. Or are you arguing that pointing a fan at a 21.5kW heat source in a closed space will cool the space?

Just put me on ignore, brother. I am already the king of it.

[DeathAndTaxes]

It was your post that got me into the thread, because you were posting some ridiculous crap about how the temperature delta between 110F and safe GPU operating temperature is too small.  After I destroyed that argument you went on to something else.  

I never claimed ANYTHING was impossible other than one can't cool 21KW of GPUs in a room with a pair of box fans in 100F ambient temps.
Nothing else.  I claimed the car analogy was bad because cars operate at temps that would destroy a GPU.  

See that is what a strawman is.  You construct a false argument and then "defeat it".
Your strawman: cooling GPU given an infinite amount of airflow in 110F is impossible (claim never made by anyone)
Your "victory": AH HA got you trolls.  Given ENOUGH airflow you can cool GPUs to x deg in 110F ambient temps.

Everyone else: WTF?   No really WTF?  Is he high or something? I don't know maybe he didn't take his meds today.

Try re-reading the thread.  Given you only NOW just realized what the claim being refuted was it is easy to see how you were off in your own universe making arguments and counterarguments on a topic only you were debating.

I do know there is nothing that makes it impossible to air cool a GPU down to 80C when the ambient temp is 43C.

OK.  I never said otherwise.  Starting to get the concept of a strawman?

[DeathAndTaxes]

You never said "you can't cool it because the delta is too small and you only have 15 fans plus an evaporation cooler it's not enough".  If you did, perhaps I would have stayed out, I can't argue with that because I don't know all the details. 

Um I did and others did and then they correct you and you kept going. 

The "enough airflow" as indicated was a pair of box fans.  So yes with enough airflow you could cool GPU with furnace air at 130F but you certainly aren't with a box fan.

Have a nice day.

[chiropteran]

Um I did

FALSE.

A long winded nothing and you missed the only point.

Car's cooling system can effectively dump the heatload because a car can operate at 200F.  That is 100F OVER ambient under worst case scenario.   If a car's cooling system had to keep car's internal temp at <140F then a car (as built today) would be insufficient to operate when outside temp is 100F+.  If a car could operate effectively at 300F it would need a SMALLER cooling system (relative to heat load) to keep temps <300F when ambient is 100F.

Car = 200F operating temp = 100F Delta T to ambient*
GPU = <140F operating temp = <40F Delta T to ambient*

On edit:
* further and likely unecessary clarificaiton because sveetsnelda is either an idiot or a troll ...
Code:
ambient in this case would be 100F input air time. The input air time he indicates is sufficient to cool his farm.  Yes it may also be cooler parts of the year but your idiotic trolling aside it wasn't your claim that you could cool the GPU with outside air when airtime if 0F your claim was you could cool them when outside airtime was 100F.

The point of the 100F vs 40F is that given 100F AMBIENT AIR TEMP it is much easier to cool something (easier as in surface area and airflow requires) when you only need to keep it at 100F OVER AMBIENT.  It is much harder (as in amount of surface area and airflow required) to keep operating temps at only 40F OVER AMBIENT.  Yes sveetsnelda I know what over ambient means.  Maybe you forgot but your claims was you could cool GPU with 100F input air.  Not sure why it is sooooooooooooooo complicated but if your are cooling something and the T-In is 100F then that is your ambient temperature.  You can't cool anything below ambient without phase change so that becomes the baseline.   A perfect cooling system could keep card temp at Ambient.  Such a system would be massive though so the Delta over ambient determines the amount of cooling (in terms of surface area, and airflow) necessary.  40 Delta over ambient is harder to achieve than a Delta of 100F over ambient for the same heat load.

The fact that a car can operate (at 100F over ambient) doesn't prove anything.  A nuclear reactor can continue to operate at 600F over ambient that doesn't mean a water cooled rig that keeps a GPU at 600F over ambient will be effective.  Why do reactors run at 600F?  Because the cooling system can be smaller/cheaper/more efficient than if it needed to operate at 500F, or 200F (car), or 140F (GPU).

40F Delta T is not much to work with.  The smaller the Delta T the more volume necessary to transfer the same amount of thermal energy and the same surface area.  If you can keep an entire farm stable 24/7 with 100F input air temps well you are better than most.  My guess is you 100F temps are with low humidity? Still your stupid car analogy is just that ... stupid.

Please show me where you are talking about his specific post.  You can't because you weren't.  You go on and on about how it's hard to cool things when it's hot out.  I think we all get the point, nobody said it isn't harder.  The point is you can do it.

[bitcool]

Once upon a time, there were six 5970s calling this little house home, their poor master couldn't afford a server room; (not) surprisingly, they all survived a N40⁰ hot summer, including a few 100+ days.

Actually they are still living there, all live and well.

[rjk]

Once upon a time, there were six 5970s calling this little house home, their poor master couldn't afford a server room; (not) surprisingly, they all survived a N40⁰ hot summer, including a few 100+ days.

Actually they are still living there, all live and well.

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0193.jpg

Epic win. No problems with rain/humidity?

[DeathAndTaxes]

FALSE.

<Snipped long post by D&T>

Please show me where you are talking about his specific post.  You can't because you weren't.  You go on and on about how it's hard to cool things when it's hot out.  I think we all get the point, nobody said it isn't harder.  The point is you can do it.

Thanks for proving the point.  I said it is more difficult.  I said it takes a larger surface area.  I said it takes higher airflow.  Nowhere did i say it was impossible.

Your blatant and obvious lie is that I said it was impossible.  Maybe you are confused but "impossible" was your strawman.  You made it up just to defeat it and beat the "trolls".  YOU claimed impossible so you could prove it wrong.

[bitcool]

Once upon a time, there were six 5970s calling this little house home, their poor master couldn't afford a server room; (not) surprisingly, they all survived a N40⁰ hot summer, including a few 100+ days.

Actually they are still living there, all live and well.

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0193.jpg

Epic win. No problems with rain/humidity?

There are 3 Cool Master full towers inside, raindrop is not easy to get inside. Humidity hasn't proven to be a problem.
One tower shut itself down a few times in hot afternoons, possibly caused by PSU overheat, so I converted it to a part-time worker.
Other two didn't have the issue.

[RandyFolds]

Once upon a time, there were six 5970s calling this little house home, their poor master couldn't afford a server room; (not) surprisingly, they all survived a N40⁰ hot summer, including a few 100+ days.

Actually they are still living there, all live and well.

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0193.jpg

But what about the poor dog, shoved out into that brutal heat?

[bitcool]

But what about the poor dog, shoved out into that brutal heat?

He gets special allowance working as a security guard and lives next door 

[DeathAndTaxes]

So your name is a lie then?

Those bits aren't cool.  More like bithot. 

[bitcool]

So your name is a lie then?

Those bits aren't cool.  More like bithot. 

lol. Depending on seasons and time of the day, I can change from bitcold to bithell.

[PulsedMedia]

Once upon a time, there were six 5970s calling this little house home, their poor master couldn't afford a server room; (not) surprisingly, they all survived a N40⁰ hot summer, including a few 100+ days.

Actually they are still living there, all live and well.

Epic! ^_^

[Global BTC]

You should paint the roof of that dog house white to better reflect the sun. Better yet: Cover it with aluminum foil

[phorensic]

Cool, bro. You can argue semantics and provide poor analogies.

How about you just explain how 'two window fans' provide an adequate volume of air to compensate for the delta-t of 40F. You do this for a living; I'd love to see the calculations.

It's a delta-t of 65.2F.  I don't run my air-cooled GPUs at 60C.  I'd like the fans to last more than a few months and I don't need the GPUs to keep running for decades.

I'm not doing your homework.  Judging by your previous posts, you'd turn mine into a conspiracy theory.  If you knew enough about the subject to understand the calculations one would post, you'd realize that a temperature differential of 65F isn't really THAT difficult to work with when you have a decent supply of fresh air.  I'm not showing you my birth certificate either.

I grow dope and fish for a living, bro. I have no idea what volume of cross-flow you would need to dissipate 21.5kW of heat with 100F ambient temperatures, nor how to calculate it.

I can say that I have dealt with ~25kw of indoor lighting, and it took a six-ton compressor working it's ass off and fans that no one on earth would call 'window fans' even when the intake temps were in the sixties(F).

Cannabis and fish together or separately?  I'm trying to get my aquaponics setup going right now, but it will just grow leafy greens and maybe peppers.  Hard to find edible fish to grow around here too, so I just have some hobby style fish.

I have set up a cannabis aquaponics system, but it's too finicky, and requires too much space. Peppers get tall and kinda bulky. You will get a lot more productivity sticking with herbs and greens. Where do you live that you can't get edible fish? Tilapia are pretty easy to snag except in Florida, and they are completely fucking indestructible.

I want to grow tilapia but they require a license here in California.  I think it's cool you actually did a cannabis aquaponics system tho!

[RandyFolds]

No way! Tilapia require a permit there? Hit up chinatown and grab some live tilapia or catfish. No one will hassle you about permits there, and I am positive you can get both in Los Angeles. The only trouble is going to be finding females if you want to breed them.

[cablepair]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

[bitcool]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Negative. I was just an onlooker before decided to post the picture. Although I was a proponent of "open air operations" in a similar thread last May: 
   https://bitcointalk.org/index.php?topic=9621.msg141748#msg141748

That being said, do you really want to pay 5BTC to see 3 boxes sitting in a dog house? I can tell you they fit perfectly.
 http://www.amazon.com/gp/product/B000QJETYS/ref=oh_o04_s00_i00_details

[bitcool]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Okay, I just went to my backyard, negotiated with my neighbor's dog, he was kind enough letting me put the fan back in, along with fake LEDs, and took a picture -- but it looks beautiful, doesn't it? 

[pla]

Okay, sick of this discussion, so I did the math.  Go ahead and carry on arguing with it, without me.

Repeating my earlier point, the average bedroom measures a mere 86ft^2, or roughly 600ft^3, Meaning a 2400CFM box fan will completely remove the air from the room every 15 seconds.  Two will then do the job every 7.5 seconds.

1 BTU will heat 55 ft^3 of air (at STP and H) by 1F.  20KW = 68290BTU/hr.

20KW will therefore heat 3755950 ft^3 per hour, or 62600 ft^3 per minute, or 7825 ft^3 per 7.5 seconds, by a single Fahrenheit degree.  Or, put more usefully, it will heat 600ft^3 by 13F every 7.5 seconds;  At 4800CFM (one full air-exchange per 7.5 seconds), that gives us a mean-over-time rise of 6.5F - Pretty damned close to my "feels 5F warmer" estimate from the woodstove.  Funny, that.

For the rest of this, I will refer to the Radeon 6990, the hottest single card (AFAIK) in common use.  Your "preferences" of running cooler than spec aside, a Radeon HD 6970 (and the 6990 just contains two downclocked 6970 Cayman chips) has a tMax of 194F.

Now we have an interesting result here - With the stock cooler and under full load, a 6990 will violate its own spec at ANY ambient over 73F.  This would make the naysayers appear correct...

But!  We've also demonstrated that two box fans will clear 20KW of heat from a room, with a 6.5F steady-state rise.  That reduces the problem to airflow at the ambient/heatsink interface.

Since we've limited this discussion to airflow, I'll limit the following to fan/heatsink combos only.  Using a halfway decent aftermarket cooler, you can drop the under-load temperature to below 160F (you can find similar numbers in dozens of articles on Tom's Hardware or AnandTech, if you like - For my exact source, I found http://www.kitguru.net/components/graphic-cards/zardon/arctic-cooling-accelero-twin-turbo-6990-cooler-review/5/ helpful in that it described the test conditions sufficiently well to extrapolate from them), for a plausible under-load delta-T of a mere 87F.

This, then, gives us a "feasibility" result of 107F at the intake, or a raw outside temperature of 100.5F.

Call that a win or a lose, as you like.  Where I live (if I didn't pay a fortune for electricity), it would put me over my "thermal budget" for two days in the past decade (no, DeathAndTaxes, not talking about winter, nor did I ever).  And I don't live in Sweden.   

[DeathAndTaxes]

I call it lose.  The claim being disputed didn't involve aftermarket heatsinks.  Especially not .... $140 aftermarket heatsinks.

20KW of 6990 @ 1KW per quad 6990 system = 80 GPUs.  $140 aftermarket heat sink * 80 = $11,200 in heatsinks.  

So using $11,200 in aftermarket coolers one could keep the cards at not so comfortable 90C.  Using stock heat sinks temps would be beyond the hard thermal throttle limit.  That at least sounds plausible.  Nobody said cooling was impossible under any circumstances.  The claim made earlier in the thread was bogus and you just proved it.  Even with 10 grand in cooling gear the cards will be extremely hot.  Mining at 90C isn't going to produce stable efficient rigs.  You also need to account for the fact that PSU efficiency declines rapidly when ambient is >80F which is going to add extra load, wasted energy, and even more heat.  

Still interesting analysis.  BTW I am building a watercooled server rack to cool 20GH/s without airconditioning in 100F temps.  Obviously I don't think it is "impossible" but you have demonstrated the claim made by up thread is impossible.  Thanks.

[pla]

Okay, I don't care to get sucked back into this, but in the interest of extending an olive branch...

You also need to account for the fact that PSU efficiency declines rapidly when ambient is >80F which is going to add extra load, wasted energy, and even more heat. 

Ambient doesn't ever hit 80C under my scenario.  It peaks at "real" ambient plus 6.5F (3.6C).  So you have no worries about your PSU or VRMs or CPU or NB or SB or anything except the GPU cores themselves.  I don't point this out defensively, but as a positive, because...

BTW I am building a watercooled server rack to cool 20GH/s without airconditioning in 100F temps.  Obviously I don't think it is "impossible" but you have demonstrated the claim made by up thread is impossible.  Thanks.

Aside from the fact that I never claimed 110F (okay, a bit defensive), you can read my numbers on a more positive note relevant to your project.  I didn't prove it as "impossible", but rather, a function of the GPU cooling device itself.  Your idea of using a water cooler should nicely get around that limitation, easily buying you another 15-20C with which to play.  That puts you solidly in the feasibility range up to an ambient of 134.5F

Again, though, you make a good point about cost.  It still makes more sense to me to just throttle your mining rigs down over a certain temperature, than to go for a complex, expensive per-GPU cooling solution.

[chiropteran]

I call it lose.  The claim being disputed didn't involve aftermarket heatsinks.  Especially not .... $140 aftermarket heatsinks.

The claim dispute may or may not involve aftermarket heat-sinks (which are availible for under $100 btw, your shopping skills suck), as the post didn't specify.  Also, the claim in dispute included an additional fan for every rig.  In addition, there was this little gem which you completely ignore-

It gets into the high 90's and occasionally the low 100's here in the summer (desert climate).  I used a small evap cooler last year during the summer

So okay.  Assuming he doesn't have the custom heat sinks is already a stretch in your favor.  But given that, you honestly don't think the addition of an extra fan per rig AND an evap cooler would be enough to compensate for lack of said heat sinks?

A quick google on evaporative coolers provided this bit-

EVAPORATIVE COOLING
How an Evaporative Cooler Works

In the Arizona desert in the 1920s, people would often sleep outside on screened-in sleeping porches during the summer. On hot nights, bed sheets or blankets soaked in water would be hung inside of the screens. Whirling electric fans would pull the night air through the moist cloth to cool the room.

That concept, slightly more refined, became the evaporative coolers that to this day provide a low-cost, low-technology alternative to refrigerated air conditioning.

An evaporative cooler produces effective cooling by combining a natural process - water evaporation - with a simple, reliable air-moving system. Fresh outside air is pulled through moist pads where it is cooled by evaporation and circulated through a house or building by a large blower. As this happens, the temperature of the outside air can be lowered as much as 30 degrees.

While I am sure 30 degrees is a bit of an extreme case, I don't think it would be too crazy to assume that an evap cooler could lower the incoming air by 10-15F, which would more than make up for the difference accounted by those oh so expensive heatsinks.

Calling it a lose is wishful thinking, or a desperate act of someone who knows he was proven wrong

[rjk]

I call it lose.  The claim being disputed didn't involve aftermarket heatsinks.  Especially not .... $140 aftermarket heatsinks.

The claim dispute may or may not involve aftermarket heat-sinks, as the post didn't specify.  Also, the claim in dispute included an additional fan for every rig.  In addition, there was this little gem which you completely ignore-

It gets into the high 90's and occasionally the low 100's here in the summer (desert climate).  I used a small evap cooler last year during the summer

So okay.  Assuming he doesn't have the custom heat sinks is already a stretch in your favor.  But given that, you honestly don't think the addition of an extra fan per rig AND an evap cooler would be enough to compensate for lack of said heat sinks?

Calling it a lose is wishful thinking, or a desperate act of someone who knows he was proven wrong

Listen, I give up. Is that what you wanted to hear? Good for you, you win. Yay. Now please drop it because this is beyond a joke. I'll keep cooling how I want to, and you can keep cooling how you want to.

Mods, could the offtopic be split off? OP, sorry for ruining your thread.

[cablepair]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Okay, I just went to my backyard, negotiated with my neighbor's dog, he was kind enough letting me put the fan back in, along with fake LEDs, and took a picture -- but it looks beautiful, doesn't it? 

lol

now I REALLY dont believe you!
I will pay 20 BTC bounty if you take pictures of 6 5970s mining in that dog house.

[bitcool]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Okay, I just went to my backyard, negotiated with my neighbor's dog, he was kind enough letting me put the fan back in, along with fake LEDs, and took a picture -- but it looks beautiful, doesn't it?  

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0196.jpg

lol

now I REALLY dont believe you!
I will pay 20 BTC bounty if you take pictures of 6 5970s mining in that dog house.

I am in.
Specify what kind of pictures will satisfy you as "photo proof"?

[Jaryu]

Wood From my Basement = FREE
Various Pipes, Valves, & Pressure Gauges (Stolen from my neighbors basement) = FREE
Hamster Wheel = $2.99 (used salvation army)
Hamster = $4.99 (Pet Shop)

Currently its getting about 1 Mhash per bag of Hamster Food
but im looking into ways to make it more efficient
(rats, mice, racoons etc)

if you guys are so smart than tell me how I can keep my latest rig cool!

at first I was giving the hamster water and then I switched to gatorade

now when I stick a anal thermometer up his ass hes registering about 50c which was still cooler than my 5970 but id like to see it a little cooler

I don't think I laugthed so hard in a long time... and not those fake LOL... but a real LOL that lasted almost a minute

[DeathAndTaxes]

Okay, I don't care to get sucked back into this, but in the interest of extending an olive branch...

Sounds good actually I didn't realize you and someone else in the thread weren't the same person.
Your analysis at least involved some thought and pointed out some bottlenecks in cooling with high ambient temps.

You also need to account for the fact that PSU efficiency declines rapidly when ambient is >80F which is going to add extra load, wasted energy, and even more heat. 

Ambient doesn't ever hit 80C under my scenario. 

I was saying 80F.  Temps >80F aren't "bad" for a PSU but efficiency starts to decline rapidly.  Likely shouldn't have switched units like that.  Hot PSU are less efficient resulting in more current adding more heat and making them less efficient.  At some point you need to consider the increased energy costs from high ambient temps.

Aside from the fact that I never claimed 110F (okay, a bit defensive), you can read my numbers on a more positive note relevant to your project.

Yeah more of that confusing two people as the same person.  Should have been obvious although you disagreed your posts at least has some factual basis to them.

Again, though, you make a good point about cost.  It still makes more sense to me to just throttle your mining rigs down over a certain temperature, than to go for a complex, expensive per-GPU cooling solution.

Which fits in to my water cooled rigs also.  If my setup provides good cooling at max load 350 days out of the year then it makes more sense to just throttle down the hottest 16 or so days (or parts of those days).  The nice thing is cgminer makes it too easy.  "auto-gpu" : true and provide a clock rate range.  As ambient increases the temp in the loop increases.  Once it gets over target temp the cgminer will start to clock down the cards.

I saw this in effect on my test rig (the radiator is way undersized for the heat load).  It works flawlessly.  So super hot days simply mean the farm in aggregate might be running at 90% of peak instead of 100%.

[bitcool]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Okay, I just went to my backyard, negotiated with my neighbor's dog, he was kind enough letting me put the fan back in, along with fake LEDs, and took a picture -- but it looks beautiful, doesn't it? 

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0196.jpg

lol

now I REALLY dont believe you!
I will pay 20 BTC bounty if you take pictures of 6 5970s mining in that dog house.

In all seriousness, or just trolling?

[bitcool]

my god

did you really just go out in your back yard and put a box fan in your neighbors dog house to win an argument on line?

I will pay 5 BTC bounty for photo proof there is six 5970s mining inside there.

I have to see it.

Okay, I just went to my backyard, negotiated with my neighbor's dog, he was kind enough letting me put the fan back in, along with fake LEDs, and took a picture -- but it looks beautiful, doesn't it? 

http://i1133.photobucket.com/albums/m586/bitcool5/IMAG0196.jpg

lol

now I REALLY dont believe you!
I will pay 20 BTC bounty if you take pictures of 6 5970s mining in that dog house.

Go ahead, order a dog house and try it yourself.
Every miners in  Canada or close to the Canadian borders  should do this   don't waste money on AC, electricty and room space.