Thing is, I have tried that in the past and it never seemed to work. What did you set your NB voltage to? I found that my memory kind of limits it because its only 1333 Patriot Gamer series. I keep getting blue screens when I was overclocked to the 3.5GHz. I'm guessing that means it was incredibly unstable? I got the 0x50 and the 0x1E blue screens a couple of times.
DRAM 1521MHz CL9 1.72V