Many GPUs on one machine

[Peter_Hucker]

On Folding, I can run three 280X cards per riser. If your GPU is faster than three 280X cards combined, it will be limited to the speed of three 280X cards. Faster cards should either be plugged in directly, or using a ribbon (directly passes all lanes), or use Boinc (most of their projects don't need much bandwidth).

[nchowlett]

Want setup, build and parts would you recommend?
thanks

I'm running 4 x NVIDIA 3060 Ti's on a mining rig (open-airflow) 'case' hooked into a HP z420 motherboard. I saw no significant drop in performance with using all PCIE slots (down to x4), via adapters (i.e. risers). Underclocked the GPUs to allow use with undersized PSU (EVGA SuperNOVA 750 GA), but moreover for much-higher folding efficiency. My estimated power cost in Aussieland is $900/year, but the room-heating effect in winter is very significant and very welcome.

Any further questions fire away!

[Peter_Hucker]

That's cheap electricity. If I bought it from the grid I'd be paying about £20,000 a year.

[nchowlett]

That's cheap electricity. If I bought it from the grid I'd be paying about £20,000 a year.

How many GPUs are you running? Core count total, etc? Are you running a Data Centre or is my estimate off?

[Peter_Hucker]

12 old Tahiti GPUs, Radeon R9 280X, you can get them dirt cheap on Ebay. I don't want to buy overpriced newer ones. 10 computers of various types, two decent 24 core Ryzens, the rest are old stuff I made from parts. The GPUs are connected with USB mining risers. They break sometimes, I dismantle them and replace the rubbish gunk and pads with 17 W/mK gunk.

[nchowlett]

Yeah, cool. Hopefully AMD do a NVIDIA and boost their GPU performance significantly via bettering the framework (CUDA, for NVIDIA) they use.

[Peter_Hucker]

I have noticed if I wanted a really fast card, AMD are severely lacking. I'm using AMD because their 2nd hand ones are cheap. If I had to pay for the electricity, I might buy different ones. But I'm using the output to heat the house anyway, so who cares?

[nchowlett]

Totally. I'm renting so can't justify the capital investment in solar as we're likely to move before our payback period starts.

[nchowlett]

Peter, you could act as a energy provider to cut ongoing costs. If people buy more efficient cards than yours and send them to you, you could setup a better performing system, no?

[Peter_Hucker]

Solar connected to the grid is a ripoff, they pay you a fraction of the value when you give it to them than when you get it back.

If any cards come my way I'd be happy to provide the power for them.

[nchowlett]

If any cards come my way I'd be happy to provide the power for them.

Great! What's your power draw from your current system, and are you happy to continue providing this amount?

[nchowlett]

Solar connected to the grid is a ripoff, they pay you a fraction of the value when you give it to them than when you get it back.

Yep, it's the same setup in Australia.

[Peter_Hucker]

If any cards come my way I'd be happy to provide the power for them.

Great! What's your power draw from your current system, and are you happy to continue providing this amount?

4kW, and yes.