I have 17X7990 in total. The core/memory voltage and frequency vary because every GPU is different. For some GPU, I can run 0.99v, with 950/1000 MHz, temperature is 70C. For others, the temperature is 85C, with 0.95V, 870/900 MHz. It depends on the position of the cards in a PC case.
I use powered PCIE risers in open case, I put extra fans to extract heat out.
The original thermal past is extremely thick. I tried to apply thin layer of thermal paste, the improvement is minimal, just 2-5 degree, as the heat sink cannot touch the GPU evenly, even after I adjusted the force with the 4 screws. That could be the reason why manufacturer apply a thick layer of thermal paste.
I use powered PCIE risers in open case, I put extra fans to extract heat out.
The original thermal past is extremely thick. I tried to apply thin layer of thermal paste, the improvement is minimal, just 2-5 degree, as the heat sink cannot touch the GPU evenly, even after I adjusted the force with the 4 screws. That could be the reason why manufacturer apply a thick layer of thermal paste.
whats the maximum number of 7990 gpu's we can run per motherboard, can you please send me your configuration, specs of the rigs etc, I have 10x7990 cards that I am looking to put maximum per motherboard. if you can some pics would be great too. Thanks
I run 4X7990 or 2X7970+3X7990. These are all 8 GPU in total. I have not tried more than 8 GPU.
The MBs are ASUS Rampage Extreme (too powerful for mining), MSI Z77A GD55, Gigabyte GA-Z68AP-D3, ASUS P7P55D pro. These MB have 5 PCIE slots or more.
I use Windows 8, Catalyst 13.4 or higher as lower version does not recognise 7990. Some MB needs 13.8 or higher. I do not know why.
Hi Thanks for the reply, much appreciated. will you pass a few more information, Asus rampage(lga2011) is too expensive too
It looks like all the ones are tested are lga1155 or above. So I suppose the lga1150 will not support these many gpu's. I only have 7990 so which of the above motherboards you tested with that combination? which processor, how much ram needed, PSU requirements etc. Did you use intel processor or AMD? which one?I dont know if this is asking too much, but it would also be great if i can get a copy of the config file.
Cheers