Unstable Q6600 @ 3GHz?

[mgcook]

unlink the RAM?

 

[Grievearz]

Try changing the multipliers. I found that my Mobo overclocks much better with a 9x multiplier and 3.0 memory multiplier. Each mobo will have certain settings that it will overclock better with than others. Mess around with different thing, don't get too caught up with that 1:1 ratio, it's much better to have a stable system.