I really needed a PSU because I bought a new whole new system but the included case power supply was not up to the task of powering my two drives and two CD drives.
I went to my phavorite philly crappy computer store expecting to pay an arm and a leg. And the guys there really don't deal with people who know about O/C a computer. I was actully suprised they had PSU's for sale.
Well I got this Future Power 400w p4 atx power supply for only 37 dollars. I figured I could take it back if it sucks. So I ran home excited that I would finally get to use my first new system in three years. And whadaya know it was outstanding. Absolutely no problems, no brown outs no nothing. And it overclocks my CPU really well. For a while I had Two optical drives, 4HD (one was a really old SCSI beast that sucked power like there was no tommorrow), 4 PCI cards, and a AGP card in it. No strange voltage dips. You can look around the net for a review of it (I read it after I bought it).