Corsair xmx2 ddr 667 mhz will not run on 945p-platnium help

Question

Hi ,
i have a msi 945 p-platnium mobo with an intel dual core d940 processor  , i had 2 gb of ram kingston 533 ddr2 and the system was stable , i wanted to up
grade to corsair 2gb xmx2 ddr2 at 667mhz , the thing is when i install the 2gb twinx paid the system runs fine all games run fine . but when i add a further 1 gb of ram
512mb * 2 ddr 2 667 mhz modules by corsair the system boots normally to windows but when i play games videos stutter a lot and there is a lot of chopyiness and fps are
of the charts .
i dont understand why is this , i think the rig should support 3 gb of ram , would do u think the problem lies , i play company of heros a lot and on the 3gb setings it stutters a lot , but when i remove the 512mb modules the system becomes normal again ,
i have tried to install them in pairs even lowering down the clocks to 533 mhz but still nothing.
again do i think i would benefit from 3 gb of ram or is 2gb xmx2 667 mhz enough for now , please help ..

Answer 1

Is there a mix of different RAMs makers within the board?
I'll move your thread to Pentium D sections for more discussions as it is not a C2D supported board.