Do you know the exact model of the memory? Link with specs? Without knowing the specs I would bump the voltage in the BIOS one level and rerun Prime95.
Personally, I run Prime95 for an hour or two between settings changes. When "dialed in" I will run for 4 - 8 hours. IMHO anything more than that is overkill.
Thanks for the info, Both sets of RAM stock are 1333Mhz CL9 1.55v. The Kingston Value RAM does not OC nearly as well as my Corsair (because of stock heatsink). So with 210 FSB and 667Mhz the RAM runs at 1400Mhz which i'm scared is to high for the Kingston. Do you think that is the case?