I've got the 965BE Phenom 2, It's stocked at 3.4 and I can get it to 3.8 rather easy, I can get it to a stable 4.0 with some tinkering, however anything above that is rather nasty. Try overclocking in the BIOS rather than a OC program, so you can properly see your RAM clocking... Also remember that large overclocking (+15%) will result in your RAM being strained harshly if it's more than two dimms in a Dual Channel Array!