Finnsopp

Hi I currently run my memory @ 303fsb with 5:6 divider. my memory is capable of running 312mhz @ 3-4-4-10. but im only able to get my pc stable @ 166 divider. can anyone of u try to explain me why i do not get better reults with my over-priced ram? I have read somewhere that the problem is not the ram itself but the memory controller on the cpu. If that is an fact, can u tell me how i could find out if it is the memory controller. how do i proceed? Please help me here guys