Uhhh you don't need that much GPU power for 1280x1024. Even a 6850 could max out games at that resolution, you'd be bottlenecking yourself. Also if you can wait, hold off until the SB chipset gets fixed and BD releases. That'll keep you in the game for awhile, buying now is pointless since it'll just go outdated.
Also when buying PSUs, don't cheap out, in the long run you'll regret it. The PSU is just as key to the entire system as the GPU and CPU are, not enough power = no system itself. Anyway, that PSU I can't find, but I'm betting it's not a very good efficency one. Stay away from OEM ones or not big branded ones. I prefer to look at XFX, Corsair and Seasonic.
For more reference or guides look into the build for 1000$ in my siggy. That itself should be good enough for gaming and if you can't wait for SB fix.