"We were really impressed with the Seasonic Platinum Fanless 520W. It achieved the feat of being the best power supply we’ve ever reviewed.
Efficiency was always above 90%, surpassing the requirements of the 80 Plus Platinum certification by a good margin...
The efficiency numbers are more incredible when you take into consideration that this is a fanless power supply."
Source: Hardware Secrets
Update: TechPowerUp loves it as well.
