it will affect how much the CPU can overclock indirectly. The lowest memory speed you can run is 2X the CPU default FSB. That is if you have a 333MHZ CPU, your ram can only run at 667MHz minimum. So if you increase your FSB to 500MHz, your RAM is now at 1,000MHz but if you RAM can't make 1000MHz then your FSB can't be at 500MHz and in turn your CPU clock will be limited by the multiplier used with the FSB limit