Nothing special really, just a ivy bridge celeron and a z77 mobo with 7 pcie slots. The mobo is a z77a-gd65, but a cheaper z77a-gd44 (i think?) works with 6 cards... Has to be ivy or 6 won't work. There's 3500W of power under my rig now, but two of the supplies are cheap 1000W'ers. They run 6 7950's at 1.125V, but not 6 280x cards at any voltage. I use a EVGA 1500W to supplement the other two supplies. I ordered 1300W and 1000W evga power supplies, one will power the mobo and 3 cards, and the other will power three cards alone. Ought to be plenty of headroom, I expect 275W from each card.
The rig is running xubuntu, as I wasn't able to figure out how to get 6 280x cards running in W8. You have to use the beta 3.11 drivers for Cgminer to "see" these cards, they show up as 7900 series with old drivers but won't ever mine.
Anyway, 3.11 beta drivers from AMDs site work pretty well. I did a bunch of reading on the net, and these settings are the best mixture of what I was able to find. I should say that these settings might be completely useless to you, but they should be a starting point. These cards all act different, I'm starting to think any results otherwise are just gamblers fallacy! Either way, I won't charge you 1 BTC for my config because I'm not that much of a douche
You will need to tweak the GPU clock speed for each card, most of mine are somewhere between 1025 and 1045.
I can lower the fan speed to 80% and still maintain ~75 degrees. I've got some work left to do with ducting and more permanent fan mounting.
The rig is running xubuntu, as I wasn't able to figure out how to get 6 280x cards running in W8. You have to use the beta 3.11 drivers for Cgminer to "see" these cards, they show up as 7900 series with old drivers but won't ever mine.
Anyway, 3.11 beta drivers from AMDs site work pretty well. I did a bunch of reading on the net, and these settings are the best mixture of what I was able to find. I should say that these settings might be completely useless to you, but they should be a starting point. These cards all act different, I'm starting to think any results otherwise are just gamblers fallacy! Either way, I won't charge you 1 BTC for my config because I'm not that much of a douche
You will need to tweak the GPU clock speed for each card, most of mine are somewhere between 1025 and 1045.
I can lower the fan speed to 80% and still maintain ~75 degrees. I've got some work left to do with ducting and more permanent fan mounting.