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OK I'm jobless, bored out of my mind and need something to do.  Obviously I won't be buying any hardware...  But I can dream can't I? hahaha  None-the-less I can play with the hardware & ampermeter I've already got.

Anyway I want to build (more like dream for now)  a cluster of machines that gets proportionately the highest Mhashs for as few watts as possible.  I also would like to get it powered by a solar array (I've always wanted to get one started...).  Initial cost isn't such a big deal, but obviously cheaper is better.

For now I want to discuss minimizing energy consumption.  I know underclocking and undervolting the VRAM of the GPU is one thing people do.  But here's a few thoughts...  Why not undervolt and underclock the NB of the mobo?  Disable all unused integrated components?  Going diskless (using boot server)?  Under clock/volt the CPU and disable all unused cores? Using DC directly (assuming a solar array or other DC source)?



I have no clue how much energy would be saved by under clocking/vloting the NB.  I guess that's what my ampermeter is for! :D

Assuming the board actually cuts power to integrated devices, it should be obvious why you'd wanna disable as much as you can. (I guess the ampermeter is good here too for verifying if integrated devices are actually powered off)

...If you boot using linux without a GUI you could get more Mhashs out of the GPU.  When I set windows to performance mode I got another 7ish Mhashs out of mine.  Imagine what Linux could do with no GUI at all!

Using a boot server, you can lose the HDD.  Which will cut-out about $60 (average price on newegg for cheapest HDD... unless you want refurb IDE) and use about 7-15 watts less per machine.  For the boot server I was thinking Raspberry Pi, because it's only $35 and uses 3.5 watts (according to wikipedia).  Going diskless also means disabling IDE/SATA controllers.

Since mining on the GPU has very little to do with CPU, you could possibly get away with the cheapest CPU and configure it to consume as little energy as possible.

Using DC directly (from batteries--no inverters), you could ditch the inefficiencies of PSUs--and even the PSU all together.  This would shave off cost of PSU, waste less energy and be one less thing to break down.


....Don't forget, every watt shaved-off is 1 less watt your AC needs to absorb! ;)
What you all think about my ideas so far?  I had a ton more ideas but I can't think of them for now.  I'll post them as I remember and I'll comback with the results of testing with my ampermeter.

It's not worth it, Bitcoin difficulty is about to explode.

Yea, I know :/   Because of the ASICs right?  I still have other purposes for building a cluster of GPUs (like rendering models, etc)

I haven't even done 1/2 of what I said above and I went from mining 86 mhashs at 145 watts to 65 watts.  When my PC is idle the ampere meter hardly picks-up 10 watts lol ....Still lots to do :D

If you're jobless,..... forget about rendering models....etc.... because obviously if you need such task, you wouldnt be jobless.

Now, go find a job and dont take our tax money.

Kthnxbye

@ Nemesis
Did you wonder in from 4chan?  You're assuming all kinds of shtuff and selectively dropping statements & all...  ...just like someone from 4chan. Like assuming I'm a leech; I'm not trying to find a job; I'm going to use the cluster for earning money (besides with bitcoin)--and conveniently dropping the fact I said this all basically a big day dream.

I think if the CPU/RAM speed/quantity is too slow/too little it affects overall performance for mining... there is a ratio of GPU memory to system memory that need to be maintained...

Did you wander in from twitter?

If you are talking about "powered by solar arrays" etc to save money, you would be better served by just buying a BFL single.

You can do a LOT to minimize power consumption, some of which you listed above. Some choices can make a huge difference in total cost of power: undervolt the GPU, underclock the GPU RAM, use 90Plus Gold or Platinum PSU @ 240V, host them in an area with cheap electric rates, supplement with solar, ect. OTOH, some features will lower power usage, but aren't really worth it: disable devices in BIOS, undervolting CPU/MB, buying a low power CPU, booting from flash drive rather than HD, etc.

Spending all kinds of time and money just to cut 10W here or there will literally save you less than a $1 per month. Undervolting the GPU and saving $15 per month? Worth it. Undervolting the CPU/NB/MB/RAM to save $0.50? Not so much.

You obviously know nothing about building and powering a PC if you honestly think this will work. Like seriously WTF?!

And this is not even getting into the discussion about how the difficulty is about to explode, and GPU mining will be unprofitable in a matter of weeks. That's a discussion for a whole other thread!  ;)

@ Everyone
I made this topic as a theoretical project to proportionately crank-out as much processing power as possible, with minimal energy consumption.  ...Taking into consideration long-term operation costs (ie energy bill), and not necessarily building a disposable computer exclusive for mining.  I guess it's easier to understand what I mean if you think of it like "because we can".

The reason I say theoretical is because I only have my one desktop to play with, and can't try some of the stuff mentioned in this thread.

No; what made you think that?


@ deepceleron
Won't undervolting the GPU core proportionately reduce mhash output per watt?  If true I don't see much point in it (assuming it needs to be underclocked).

Anyway, I found undervolting the CPU, RAM, NB & SB to be quite effective.  I've gone from 145 watts to 53 watts (both measurements are when mining).  I'm getting the same hash rate while consuming 273% less energy--or saving about $10 per month (theoretically >$20 because the AC has to spend more than that to remove waste heat from the room).  And I've yet to disable on-board devices. ...though I'm not expecting to go much lower than 53 watts--heck the GPU alone is supposed to be 50 watts (says the manufacturer).


If you use appropriate components there's no reason you can't run on batteries, inverter-free.  You didn't think I meant plugging the PSU or something directly into a battery did you? 

Here's something pre-made if you don't believe me: http://www.short-circuit.com/product/M2-ATX-HV.html  ...Not exactly best suited for this discussion but still proves it's possible.

...And the reason I want to squeeze every watt out of the computers is because it's part of what I desire from the project :)  Less energy consumed means smaller/cheaper solar panels and batteries. 

Think of it this way... Say we've got a cluster of 10 computers.  let's pretend my results are typical and all of those computers' consumption can be reduced by ~92 watts.  That'd be cutting 920 watts.  In a world where thermal dynamics loves us, we'd spend that again for the AC to remove the waste heat from the room.  By cutting each PC by 92 watts, it'd essentially be cutting total consumption by 1 840 watts--or saving about $198 (at $0.15 per kwh) each month.  Suddenly killing a watt here & there don't seem so bad does it?  However that's assuming you're paying for power and have no panels set up.

How about buying CPUs, motherboards and RAM that use less watts in the first place?

The scope of this project seems artificially constrained right from the start. You just want to do stuff that interests you without exploring more practical alternatives.

@ BeetcoinScummer
In what way is it artificially constrained?  My goal is to try to determine a method for getting most hashs per watt, in a proportionate matter--as in, a GPU that mines 100 Mhashs for 80 watts would be more desirable than a GPU that puts out 200 Mhashs for 170 watts.

Same applies for motherboards.  A mother board that has 4 pcie slots and consumes 50 watts, would be more desirable than a mother board that consumes 30 watts, but has only 2 pcie slots.  (fewer GPUs per system)

Coincidentally a system that'd perform well with bitcoin would do great for most everything else I'd use it for--which is why I don't want to invest in ASICs.  If you're talking about not considering ASICs as being constraining, then yea you're right...  it is constrained

EDIT: I want to take it to the extreme and find ways to squeeze-out even more efficiency.  Like taking mobos that draw low current and finding ways to make them draw even less

Not to be offensive but a little late to the party aren't you.  There is no point in trying to optimize any machine that pulls in less than 60GH now.  In 2 weeks your work will all be undone by a difficulty spike not seen since 2011.

Everything you are trying to do has been posted here before, and people have documented it to death over the past 3 years - use the search feature.

The lean green hashing machine is either called an Avalon of BFL (BFL being leaner but not available currently).  Look into one of those 2 and get on the buy list now.

You you're jobless and want to keep the costs down, but you're talking about spending all kinds of money on custom inverters, solar panels, and then the actual cost of the hardware! If you're really interested in the most MH/s/W, check out threads like THIS (https://bitcointalk.org/index.php?topic=76685.0).

Come to the litecoin party over at alt. chains, we need miners.