I'm somewhat confused by the above comments. I spent $40 on a 500watt PSU about 3 years ago and it's been working perfectly ever since. I don't remember the brand, but it hasn't had any problems.

As for the OP, congrats! I have a more-or-less identical system, and it's great. Actually just installed XP on it over the Vista that was there, and it's really fast.

A note though - OSX86 had problems with almost all nVidia graphics cards I've tried.