Look for some sort of a RAM Divider in your BIOS. It will probably say something like DDR2 800, with options of DDR2 667, DDR2 533, etc. Depending on the amount of overclock, you'll need to adjust that to something along the lines of DDR2 667, unless the BIOS offers anything in between 667 and 800. Setting it to DDR2 667 should do the trick if your FSB is <= 240.