I bought a gaming desktop off ebay. It's a core2 Duo E8200 CPU 2.6ghz. Gigabyte Ep43-DS3L DDR2 motherboard. AMD Radeon HD 7770 GPU, 2x2GB DDR2 single channel RAM (DDR2-400). It has a single HDD and a CD/DVD burner. The PSU is the Cooler Master 500Watt Extreme. Is this PSU good enough to handle the overclocking? The seller says he overclocked for a few years, and had no problems. I had to replace the CPU Cooler with a Cooler Master Hyper TX3, due to poor shipping/packaging. So I'm kind of nervous about overclocking, as I've never done it before and I don't know if I need to upgrade the RAM first. Thanks.