To OP:
The set up you named at the start is practically my set up, except i only have an older CPU (E6420), and a 500w PSU (although it is Antec)
But let me tell you, it runs very very well for the price. I can run Crysis on medium with no framerate issues, and on high with only a little slowdown. It also runs games like COD4 flawlessly. I wouldnt really worry about downgrading to the 600w PSU, and that way you can buy yourself some more ram, or a nicer case.







