how do you make evga overclock setting stick?

[RayEarth]

I just got my evga 5900nu today, installed the 52.16 and used coolbits to get the overclock tab. The auto-detect gives me an 442/932 overclock but it never sticks long. I manual set it to 450/920 but only the core stays at 450 while the memory always goes back to 850. Am I missing any steps?