the 9800 and the 250 are almost the same card. the 250 is like a rebrand with a few extra features. you should be find with a 600 watt PSU as long as that power supply has the write cables. Im running that exact card by BFG the GeForce 250 GTS, its a preddy solid card and i can run most games at max graphic's settings at 1920x1080p. for the acception of FarCry 2 and the Crysis Pack, I have to tweek a few of those graphics settings down 1 notch from the top. Im also running a 700watt Gaming PSU and im overclocking and everything with no power problems.