I just built my first comp with the following components:
E6600 with Ninja
Corsair XMS 2x1gb
The cooling set up is as follows:
1 Yateloon in the Front pulling air in
1 Yateloon on the Top of the case
1 Yateloon on the Back of the Case
1 Yate Loon Mounted on Ninja
I used artic silver 5 on the Ninja and I'm sure its seated properly, I have not OCed at all. The fans are all running at 1100-1200 rpm. I am using Intels Thermal Analysis tool (TAT) to put full load on both cores.
First. make sure you didn't use too much thermal grease. If that's not the problem, then your best bet would be to lap your heatsink and cpu. Most if the C2Ds heat spreaders are concave to some degree. However, lapping your cpu voids the warranty. So you may just want to only lap the heatsink first and see the results.