I have an Antec 350w PS and I have a p4 2.26@2.8, 1 gig of ram, geforce 4600 @ 330/740, sb live value, WD 120SE and WD 250SE, Nec3520a and some sony dvdplayer. I've never had any problems with not being able to pull enough power. I'm pretty sure my system would use a hell of a lot more power than yours. I'm always gaming with it.