Oh sorry....referring to the P5N-E again.
OK theres a way to set the FSB and RAM speed manually. To do this, go to the Advanced section, then JumperFree Configuration, then set the AI Tuning to AI Overclock. Set the System Clock Mode to CPU/MEM manual-mode, and you should be able to set the FSB to 1140, and the RAM to 570, for a 1:1 ratio.