600W is probably borderline - depends on the quality of the PSU
the power draw is quite increadible - I mean mine was just pulling 450W even in New Vegas .. which is very impressive - more than I had with a 3870x2
but nice at idle - less power than my 4890 was
It's an OCZ StealthXtreme 2. Might have to go with something a little less power hungry if I'm likely to have issues....