Quote from: Bolchevickos on September 12, 2017, 07:17:47 PM

Hi,

I have the project to build a second mining rig. For this one I would like to use 12 RX560 with 2 GB of memory.
I was hoping to find some help and answers to a few questions I have.

For the motherboard I was planning to use the Asrock H110 Pro BTC+, I think there shouldn't be much issues to get the GPU work in Linux.
The main concern I am facing at the moment is how to power the thing. @40W/gpu, 800-1200W would be largely sufficient. I was thinking about connecting 2*600W PSU.
The problem will still be to get enough PCI 6 PIN power lines. I do not know any power supply in this range providing more than 2-3 lines. I saw there was some splitters, do you think that could do the trick? Even If I split one line into 4 others, the power draw would still be quite low into theory (<200W)? Would that work?

Similarly, would you see any issue with splitting the MOLEX?
I am very open to any other suggestions you may have.

Many thanks for your inputs,

Bolchevickos.

Do the RX560s really only draw around 40W/card? I was under the impression that it was closer to 70-75W.

Anyhow, if all of your cards are use 6-pin connectors, you would probably be fine using an 8-pin PCIe to 2x 6-pin adapter with the 6+2 connectors on the PSU(s) you buy. Most PSUs have either one or both of the PCIe power connectors as a 6+2 pin connector, making the cable have either 2x 6+2 or 1x 6+2 and 1x 6 pin. Combining either of those configurations with one splitter lets you connect power to 3 RX560s.

The PSU cable should definitely be able to handle the load of 3x RX560s, since it should've been made to handle powering 1x 8-pin and 1x 6-pin (or even better, 2x 8-pin) connections simultaneously.

This is an example of a splitter that would do the job (note: I am not necessarily recommending this specific adapter. Do your own research and get a high-quality adapter with good cabling):
http://www.ebay.com/itm/PCI-e-8pin-to-Dual-8Pin-PCIe-8pin-2x-6-2pin-Graphics-Video-Card-Power-Cable-R-/172783728372
I would strongly suggest that you avoid using something like this as a 1x 8-pin to 2x 8-pin splitter, however. That might be pushing it. For this purpose, you'll only need to use it as a 1x 8pin to 2x 6-pin adapter.

Question: What risers are you planning on getting? 6-pin powered ones? 4-pin molex? SATA?