Cannot for the life of me get 6 x 580 working in Windows 7 x64, I've tried the 6GPU mod (in admin mode) multiple times, Still only 5 of the 6 GPU's work, 1 shows code 43..
H81 asrock pro
It's possible to get 6 GPUs running in Windows 7, but may be easier with Ubuntu if that's an option for you.
If you're not a Linux user, Windows 10 might also work better. (I'm not telling you how you should obtain Windows 10, if you know what I mean.
)
If you're talking about the 6x GPU mod linked here:
https://lbr.id.lv/6xgpu_mod/6xGPU.htmlI've used it successfully before on Windows 7 with 6 7xxx series cards, but never with 580s, so I don't know if the more recent drivers will allow you to use this modification. More likely than not, they won't be compatible, unfortunately.