Thermaltake makes some nice power supplies. Something like this..
http://www.thermaltake.com/purepower...0049atx12v.htm would be awesome.
As for benchmarks you could check out
www.futuremark.com and get 3dmark2005, and/or PCMark etc. You could also just do some benchmarks on some games like Doom3 and Farcry or something.