Quote Originally Posted by KILLER_K View Post
The megahalems has wide spaced fins, so a high rpm, static, cfm fan is not needed. If you look at a true the fins are pretty close together resulting in needing a higher rpm, static cfm fan to get the air to flow through it better.

As noted before the large fins when using two for push/pull set up will only cool maybe 2°-4° better. And in some cases if you have a larger static pressure fans they will cancel out each other and make higher temps.
Adding a high CFM Sanyo Denki made a massive difference for me. 4.2GHz wouldn't boot w/ a ~60CFM 25mm fan. Adding the SD, I was able to get it 16 hour LinX stable.