Unfortunately George, you can't do less than a 1:1 FSB : DRAM ratio on this board (or, unless I'm mistaken, any P45 board). Your only option to get to 500 is faster RAM or figure out how to get yours to DDR2-1000. In case you need one person's reference, I had Platinum Rev.2 for a while on a P35 chipset board. The max I could get stable was DDR2-980 (with 2.2v & 5-5-5-15-42-2T timings) and max boot was ~DDR2-990.