i have a P5LD2 motherboard which as far as i can tell has a max fsb speed of 667. right now i have 2x1GB ddr2 667 ocz gold sticks. my computer runs tf2 really slow and i want to switch to vista or 64-bit xp and add some memory. i have 2 slots available. i dont really want to get 667 ram because i want to upgrade a lot of other stuff in the coming months/year. is it possible to get some ddr2 1066 or 1333 sticks and add them to what i have if i lower the speed in bios? if not can i just replace what i have if i slow them down? then i would have them available when i upgrade my motherboard in the future and i can speed the timings back up.