So... I know the title is dumb, but I'll explain.

Me and a friend of mine are building a 5GPU rig with 5 xfx 580 4gb, 1200w Chieftec Power supply, and motherboard http://prntscr.com/hthn8m
The problem occurs when I boot the system with 5gups. The GPUs start working, but windows ( win 10) never boots. I partially solved the issue, by removing 1 GPU, booting it with 4, and works perfectly, and then added the fifth, and again works well. But I tested it , and again, if I have to boot it with 5 gpus, it doesn't work. So its kinda impractical for me to remove than plug in the fifth one every time electricity goes down or the rig goes off...

Any suggestions? ( I haven't done anything to fix the issue as I don't know what to do )

P.S: I have the same setup on 5 rigs, all 5 have the same issue.