X-bit Labs reviews 6 1000W PSUs from 6 different manufacturers.  Every single one has the power to run even the most cutting edge performance PCs, and they do so within acceptable electrical parameters.  One of the deciding factors turned out to be the fans.  Those that were cooled by 80mm fans tended to become uncomfortably loud when stressed, but the 2 models with 135mm fans were quite acceptable.  This review covers a lot of tests for each PC, so make sure you have some time to read through it all. 

Soon you’ll be needing a dryer or stove outlet to power these things, but not quite yet.
“Today we are going to introduce to you the first batch of the most powerful PSUs in the today’s market: 1000W models from Cooler Master, OCZ, PC Power & Cooling, SilverStone, Tagan and Topower. Find out which one is the winner from our detailed test session!”

Here are some more Cases & Cooling reviews from around the web:

Click Here to go to Cases & Cooling   CASES & COOLING