Memory overclocking problem

I have tried overclocking the ram on my machine and keep winding up with crashes. My machine runs stable at ddr200, but the board (shuttle as45gt) is rated for ddr333 and ddr400 unsupported but the settings are still there. I'm using kingston value ram pc2700 but have tried corsair xms and OCZ performance ram with similar results. I have tried scaling up the voltage on VDIMM and VDDQ tried all the settings to the highest and i can get about 1 hour out of intense gaming before it crashes. HL2 gives me a memory error, call of duty just crashes to desktop. Cas lat is at 2.5( because that is what the ram is rated at) and and i have tried 2 and 3 with no better results. I have tried to game with the cmd rate at 1t and 2t and auto and various combinations still crashes. I have ample cooling inside my case. I have the latest bios and drivers for all my hardware and software, i'm stumped as to why my machine is so stubborn with aggressive memory settings. It would be nice to game at ddr333 because i would get another 400 points on 3dmark03 and much better frames for all my games.

 

It almost sounds as if your mobo is choking at thows speeds insted your ram ...

I have 2 sticks of DDR 500 but i can only run them at 450Mhz because my mobo cant take it ....

 

Yeah i figured as much. I guess i can try to shoot for a midrange increase of 266, guess its back to the drawing board and more play testing.