I installed a Scythe Ninja Rev.b. I had to push it down slightly as it was barely hitting some fins. If I wanted to rotate it 90 degrees it fits no problem, but then the bottom aluminum fins are not in the direction of the fan. I used the Thermalright LGA775 Bolt-Thru-Kit and it was a breeze. In the future I will not have to take the motherboard out to change my cpu.
There is a thread on this at the Asus P5E Forum. http://vip.asus.com/forum/topic.aspx...ge=3&count=257