Triple 6990 under windows

[bbminer]

Is it possible to run a 3 card 6990 bitcoin mining system under Windows? I am seeing a lot of guides for linux. I would prefer Windows if it's possible.

Thanks

[allinvain]

Nope..I'm afraid not. 3 6990s = 6 total GPU cores. Windows can address only 4 max.

Maybe it might be more efficient and cheaper to run 2 separate rigs with 2 x 6990s?

[haploid23]

Nope..I'm afraid not. 3 6990s = 6 total GPU cores. Windows can address only 4 max.

nope, this is totally wrong. i was folding with 3 gtx295 in the same rig, for a total of 6 GPUs in win7 and XP. you can do the same with HD6990. i think you're confusing it with SLI and crossfire. you can't SLI or crossfire more than 4 GPUs, but that would not apply for mining anyways

[allinvain]

oooppss...yes my bad I was indeed confusing it with crossfire..

as a side note under linux you can see 6+ GPU cores..I've seen some 4 x 5970 rigs..

[1.21gigawatts]

Windows can only support 4 ATI GPUs.  I am not sure what the limit is with Nvidia, but that's the reason why you were able to get Windows to recognize 4+ Nvidia GPUs

[allinvain]

Aha! So I have been vindicated. Well I should've had more confidence in my own words.