I am trying to set up 4x7950
gigabyte windforce v2 flashed bios for 1.090v
13.3 beta
cgminer 2.11.3
w7 64bit, 8gb in a sigle stick
pci risers x1 to x1 to the cards
At the moment I have 3x on a cheap gigabyte mobo which doesn't recognize the 4th card (shorting not attempted)
I bought an MSI Z77A-G45 and I will try it tonight to see if the mobo is the problem, I hope so
I use an xfx 1250w gold, 3x at 1000/1250/+20% run stable at 750w from wall
I can run stable each card individually to 660kh with 1125(55)/1450/+20% I 19 tc 16384, with or without risers.
When I put 3 together I cannot go over 595-605kh each, (600/550/600 reported on pool) with 1000/1250/+20% temps about 65-72c with fan 60%
At the moment I run guiminer with this cmd:
cgminer.exe --scrypt -u x-p-x o x --gpu-platform 0 -d 0 -w 256 -v 1 -I 20 -g 1 -l 1 -T --thread-concurrency 21712
cgminer.exe --scrypt -u x-p-x o x --gpu-platform 0 -d 1 -w 256 -v 1 -I 20 -g 1 -l 1 -T --thread-concurrency 21712
cgminer.exe --scrypt -u x-p-x o x --gpu-platform 0 -d 2 -w 256 -v 1 -I 20 -g 1 -l 1 -T --thread-concurrency 21712
I know a lot of people can keep 1 card at 660kh stable, I also can but what about 3 or 4 cards?
What's your hashrate/clock/mem with 3 or 4 7950?
Why do I get mixed results between 1 card and multiple cards? is it the mobo which cannot keep it ? or maybe the psu (I doubt this)?
I want to squeeze every single hash from these cards, I know 1750-1800kh is good for 3 cards but I am more looking at 650kh each card.
So, is it possible?
Thanks
