Quote from: dzzima on February 11, 2014, 10:14:46 PM

guys... just tried to put 4 7900 into on rig - failed. I use 1-16 powered risers, two PSU 1250 and 1000w. My win7 sees only 6 GPUs, one of them work on low memclock/gpu regardless of MSI afteburner settings. I tried various slots on my MB ASrock FM2A88X Extreme6+ - same results. Any ideas?

I use Win8 for my rig using several version of Catalyst>=13.4. Maybe you can try that.

Or you can use mod version of catalyst.
7xGPU + Windows // modding AMD video driver is the answer?
https://litecointalk.org/index.php?topic=11761.0;topicseen