Hard to say if drooping the RAM frequency alone would stabilise your system.
I would recommend testing for stability in stages.
Try dropping your CPU multiplier to 6x, raising your FSB to 333 Mhz and putting the RAM at a 1:1 ratio to the FSB (lowest possible setting).
Also, check and make sure your timings and voltage for the RAM is set to the manufacturers specifications.
Test in windows with dual instances of
prime95 using small FFT's.
If everything is stable, you have just shown your motherboard to be stable at that FSB.
Next, raise your CPU multiplier to 9x and retest.
3.0Ghz is an excellent overclock for your CPU and, with out any voltage adjustments, is about as high as you can take it.
If it tests stable again, try for the 10x multi for a full 3.33Ghz.
After you have the Mb and CPU stable, you can start tweaking the RAM.
Start at 800Mhz with recommended timings and voltage.
Test with
memtest86+ for stability.
When it is stable, you can start tweaking the voltage and timing settings to get every last ounce of performance from your setup.