can still be worth it, what is the rental amount? consider that 7 of those thing can do 2.2k+ a month depend on btc value

even if you pay 500 for the rental you should come up with 1700 net or minus consumption

still only month to roi, I would try to gamble with this, seeing how the investment isn't too big

I'm reading a lot that the GPUs are being produced for mining only purpose but I haven't seen a trusted website that has said this.

But I think that this can't be completely true, as they will produce also gaming GPUs at the same time but will maybe be focused more in the mining part and in the power efficiency to spend less power.

what is your electricity rate? this will make the big difference here, if 5 cent then yes, go for antminer s9, you will roi fast and a good profit is awaiting you after that

if it's high better to look at a mining rig in the altcoin section that can be profitable even with 50 cent electricity

i would not suggest to buy over mining ever, especially with current profit, only someone who can not do mining because of other reason like space very very high electricity etc, would do a wise decision by buying instead

Oh Lord...
And where does the cold air come from? Another dimension? No -- there are always intake vents where warm/hot/humid air is sucked from the rooms/area which leads into the A/C system where it is cooled and dehumidified then blown out again...

Since you refuse to heed what experts who do this for a living and are trying to educate you in the basics have to say, now the Willfully Clueless Dreamer Ignore button is activated.

 
And to assume that someone who has designed/built sealed enclosure multi-kw power electronics systems for decades which utilize either chilled water or mechanical cabinet coolers to move said heat loads elsewhere does not know 'what is possible' and what can actually be done is simply dreamy-eyed ignorance of the laws of nature. Some folks here <raises hand> design high power industrial electronics systems for a living, others work in HVAC systems and some in other specialized fields. Not many perhaps but there *are* technology experts here. Point is some folks here DO know what is possible with today's technologies and what is not-possible even with tech upcoming in the foreseeable future..

Yes it is easier to remove heat from dry air per-cubic foot moved but that is because the moisture itself holds a substantial amount of Latent Heat to begin with. By the same token, cool somewhat humid air is better at cooling things/people because it can absorb more heat with a lower rise in temp vs dry air.

Problem you do not see is that, great: You are using a separate dehumidifier to remove the moisture (and additional heat stored in the moisture). Fine. Thing is - you are using energy to pull out x-amount of moisture per-hour and that takes a fixed amount of energy to condense out. Doing that with a separate dehumidifier ahead of what the main cooling can do is less efficient simply because you are now using another point of mechanical effort instead of the 1 one big one. If properly sized the 1 big A/C unit will remove the humidity AND still provide proper amount of cooling all the while consuming less additional power vs running 2nd motor.

Perhaps you should read up a bit on Thermodynamics along with some textbook on heating/cooling principals 101?

TANSTAAFL

That said, a portable A/C unit like this which draws in outside air for the hot-side and exhausts the heat to the outside using ducts http://www.globalindustrial.com/p/hvac/air-conditioning/commercial-portable-ac/industrial-portable-air-conditioner-2-ton-w-cold-air-nozzles-21-000-btu-230v?infoParam.campaignId=T9F&gclid=CJf189LJvdQCFZ23wAodJP4Ldg would certainly work -- at the cost of using more electric but at least you won't be screwing with the building HVAC system.

 Most likely the central air will be mechanical A/C, not evap.

 A dehumidifier *IS* a mechanical air conditioner, just with a "humidity control" type setting - they do NOT "save energy".
 There is ZERO point to using one in a situation with a central A/C, unless you are overloading the ability of the central A/C setup to cool the room the miner is in.

 It means that air conditioning can't keep up with the heat generated by their rigs.

 1000 watts of rig generates about 3400 BTU of heat - that's a level of power often exceeded by multi-card rigs PER RIG, only needs 8 rigs to generate more heat than a 25,000 BTU window A/C CAN remove (and 25k BTU is HUGE for a window unit, most are quite a bit smaller in capacity).

 Just to add insult to injury - that 25k A/C unit will probably need another 2700-2800 watts of power to run IT, at common 9.x SEER efficiency rating range of most window units - though on the positive side most of THAT heat gets exhausted to the outside and not into the room.

 Central A/C is commonly rated in "tons" of capacity for historical reasons - a "ton" equates to 6000 BTU, and a LOT of central units are in the "5 ton" or less range, which is still only 30k BTU or less.
 Large building central A/C units will be quite a bit larger - but they also have to provide A/C for a lot more space, and a lot more heat-generating humans and lights and computers and .....


 TANSTAAFL
 (There Ain't No Such Thing As A Free Lunch)


 Some "portable" dehumidifier units have a duct to exhaust the hot air they produce to an outside area. I want to say "most or all" but I've only worked with a few of those type units.

So, basically, Linux or simplemining cannot undervolt as well as windows can, and thus, it will use more watts than windows. Correct me if i am wrong please?
How much watts roughly can an Rx 470/570 on simplemining get compared to windows??

Overclocking - simple. Undervolting - see my last post on this, please:

Overclocking - simple. Undervolting - see my last post on this, please:

Evaporative A/C works by flowing air through some sort of "media" that has water on it.
 
 If you don't exhaust that humid air, it just keeps building the humidity level in the air 'till the water stops evaporating - and when the water stops evaporating, it stops cooling anything.


 If you are flowing air through a room, you can place a standard mechanical A/C unit (or the outlet for one on a split-phase or central unit) in such a way that it directs it's cold air into that flowing air, causing it to cool some.



 Specific areas in the West that are arid or semi-arid climates (most of Arizona and New Mexico, central Washington state, the Imperial Valley and Mohave Desert areas of California, among others) will have fairly widespread usage of evaporative cooling, but most areas use mechanical A/C.

 I am not aware of a "central A/C" setup for a large building that uses Evap cooling, but I suspect they exist - I have seen such setups for small buildings and homes.

 You could put your miners in such a position that the exhaust from the miners points at a return air duct, if such exists, for your building's central A/C - should help keep the temperature in the room lower while the A/C is flowing air.

 Depends on the building - some have louvers in doors for return air via the hallways, some have ducting for return air.

a) A GPU miner with multiple cards for altcoins can use just as much power as an ASIC-based one for BTC. Watts are watts....

b) As for "Now, is there a need to still remove the hot air in the room that is generated by the GPUs??"
....   Hot air?? WTF do you think the A/C is doing? If the air temp in the room is still hot then the A/C is too small.

What is so difficult about grasping the concept of needing to know how much power (heat) you are putting into the room to determine how much cooling is needed to remove said heat? Power used and cooling needed to remove it are joined at the hip, 1 sets the limit to the other.

You really need to think through what you are doing before asking the same question over and over. Stop with the 'can add more' and apply NUMBERS as in how much power is available in KW and how much cooling is available in BTU. Only by knowing at least one or the other can you start getting an answer.

*IF* you are using standard mechanical air conditioning to cool a room, you don't need to have ventilation.

 You DO need to have BTU capacity in the A/C to at least match the BTU heat generation of the gear in the room in such a case.


It's possible to set up an A/C in such a way that it puts cooler air into the "cool side" of a ventilation system, but that's NOT the norm for standard mechanical A/C systems.


 If you are using Evaporative cooling type A/C, then you DO need to be able to vent the air out of the room.


 GPU mining can use just as much power and generate just as much heat as ASIC mining does - though most GPU rigs *PER RIG* use less power than most current ASIC miners, the TOTAL wattage/BTUs still adds up.

Then the question becomes: How many miners (Watts) are you looking at and what is the cooling capacity of the A/C for the room?

Just having A/C is a fine start but it MUST be sized to the heat load being moved In most cases A/C for a general-purpose room is only as much as needed to keep it comfortable and does not take into account having several multi-kw heaters in it! I hope it does not have to said that the cooling capacity must exceed the miners heat output otherwise temps go up...

For your and others ref since most folks seem to have no idea how to search, 1Watt= 3.41BTU. Assuming a nice round 1,500W per miner, say an s9, that means 5,155-BTU of heat produced from each one.

As probably all have and will say - AC is useless for this purpose

Need air movement

Fresh (cool) air should be drawn in to your mining room and stale (hot) air should be sucked out

This principle can be displayed by opening a window/door on either side of your house and let the wind do the work (depends if your location is windy enough).

If there is a huge amount of heat being generated then add large fans to enact the above