Originally Posted by Logical_AND
I see you have an 850W PSU but won't two GTX-580s pull 600W total? That's only leaving you with 250W for the rest of the box. Getting very close to a signal-to-noise-ratio that will lead to intermittent BSODs and restarts.
I used this link -> [URL="http://www.thermaltake.outervision.com/Power"]Thermaltake PSU Wattage Calculator
[/URL]. This Calc has everything you can think of covered. I loaded everything the box has including my 5 USB devises.....I'm safe at 850W
My other system I used Thermotake 1200W PSU that one I had Triple Crossfire ATI 5970 on Water + 5870 on air, tons of lights, Water Cooling, 3 HD's, 2 Opitcals I wasn't taking any chances and went with biggest PSU at the time.