Noctua NH-U9B SE2
 

Noctua has taken their NH-U9B cooler, which already offers great performance, added a second 92 mm fan and upgraded its mounting kit. Noise levels are still at a minimum and push the envelope in silent high performance cooling for modern processors. Today we see if these improvements have made the NH-U9B SE2 even more worthy of your hard earned cash.

http://www.techpowerup.com/reviews/Noctua/NH-U9B_SE2