Zalman ZM1000-HP 1000W Power Supply
 

Zalman's new ZM1000-HP power supply has been designed with fan noise in mind. The heatpipe experts from Zalman have stuck two of these inside their PSU and added a slow running 140 mm fan on top of that. This winning combination results in one of the quietest PSUs we ever tested, especially considering it delivers up to 1000W of power via six independant 12V rails.

http://www.techpowerup.com/reviews/Zalman/ZM1000-HP