I just recently upgraded to another HD 6950 to my setup, for the CrossFire and whatnots, and I think maybe my powersupply (although it should be completely good for this setup) might be the problem here. I have to unplug all my case fans in order for my computer to start. Although, even in heavy duty games, the computer runs perfectly, nothing out of the ordinary, but as soon as I plug in my fans, I either get the Blue Screen or my computer just starts to mess up (screen wise I mean). I currently have a Corsair GS800 with 66A on the 12v.
How strange, just plugged back in everything, and It all works right now, without any problems at the moment. The only thing different I did this time was plug each fan into a separate connector from the psu rather than the extended connectors that they each have on them. Will be back if anything bad happens. And, just out of curiosity, my psu is more than enough to handle this system right?