I'm buying a gaming computer in the next few days and i need to know how much of a power suppply i need. here are the specs for the computer. Intel Core 2 Duo Processor E6700 (Quad-Core Supports) EVGA nForce 680i SLI Chipset 2 Gigs of corsair-value memory (isit worth getting muskin or a heat spreader?) NVIDIA GeForce 8800 GTX 768MB 320 GB hard drive @ 7200 RPM If you could give me an idea of how many watts i need that would be great. thanks!