whats holding back my fsb????

I can boot as high as 210fsb but it wont pass prime95. I just got a new stick of pc3500 ram from hardcorecooling.us and it will go run memtest fine up to 205mhz. My corsair would run memtest up to 210 but would not pass prime. Ive done the vdd mod so i dont think its the chipset that is limiting me. So do you think i should try a better brand of pc3500 or what????

bump

im going to test the memory async to see what it can run at

bump again
I think i figured it out. I tested my ram async at 218mhz and it passed memtest just fine. It must be the motherboard chipset i guess. I dont know if more cooling would work or what. DO you think that 1.85v on the vdd is TOO much mabe 1.7 or 1.75 would work better, I may try it just to see what happens.