I just bought a dell 4700 on ebay for $170. It is shippin with Vista home premium(I know XP is better for gaminI jg, but beggars cant be choosers). I also bought two sticks of ram (CT448359 2GB kit (1GBx2), 240-pin DIMM Upgrade for a Dell Dimension 4700 Series System) that I'm about to pop in. There is a NEC DVD burner and a 160gb 7200rpm sata hard drive consuming power as well. The 4700 is running a 3ghz pentium 4 with the stock motherboard and power supply. Can I jut pop in a geforce 8600 GT or GTS? Or will I need to upgrade the power supply? If I wanted to upgrade to a geforce 8800 GT or GTS would this power supply from newegg work? Antec earthwatts EA430 430W ATX12V v2.0 Power Supply 100 - 240 V UL, CUL, FCC, TUV, CE, CB, C-tick, CCC - Retail Or would I have to pony up the cash for this one from new egg? Antec earthwatts EA500 500W ATX12V v2.0 Power Supply 100 - 240 V UL, CUL, FCC, TUV, CE, CB, C-tick, CCC - Retail Is it hard to upgrade a power supply? My hardware experience is limited to installing graphics cards and RAM sticks. Am I going to brick my new toy? Is that 3Ghz pentium 4 going to bottleneck the 8800 down to 8600 standards anyway? Those 8600's are going dirt cheap(around $50), if there's not going to be a sizable difference I may just go with that. Looks like the 8800 Gt is going for around $150. Also...cooling? Any suggestions? I hear the 4700's heat up pretty quick.