I have 6 cards per rig, 3 of them on powered risers... two rigs... 3 Seasonic 1250 Watt gold power supplies. Each power supply powers 4 cards.
I have the Gigabyte 990FXA-UD5 and the MSI 990FXA-GD80 and they both can handle 6 GPU's I believe (still waiting on 1x risers to arrive). It looked like they had been out for awhile so I didnt know if there was anything better on the market that most people were using or not.
Newbie question...
You have at least one PSU supplying PCIE 12V to 2 different rigs at the same time?
From my understanding, all the PSU's need to have GND tied together so that the 12V is not floating in a different spot between them. You wouldn't want to have a significant potential difference between any of the 12V legs or that could fry somthing (from my understanding).
I have spare PCIE power from a G1600, but didn't want to connect it to a second rig because I was worried about this.
Can you confirm how the 3 PSUs are shared on the 2 rigs? Thanks