My PSU.

Powers my nForce2 board, two Seagate drives, two optical drives and my 6600GT, a GPU notorious for its ridiculous power consumption. The 7 series remedied a lot of the power problems with the 6 series.

I've had no crashes or lock ups and speedfan doesn't report any dramatic power surges on any of the rails. It's been good.

I'd also look at getting a dual rail PSU as each rail has it's own amperage and can be dedicated to certain components inside you machine. My GPU has a dedicated 12V rail with 18amps.