memory runs at whatever you set your fsb and dividers/multipliers to. I think the 675 might just mean it *can* run at that speed, but i doubt it will by default. even if cradivonyk's sticks are showing 335mhz with the system at 100% stock and all components picking their frequencies automatically, that is ddr2-670, not 675. i'd just get the ddr2-667.