CPU FSB and Memory Speed?

CPU FSB and Memory speed are two different things. They operate differently. It doesn't matter if you buy a DD2800 or a DD2667 or DD3 memory for that matter as long as your motherboard supports them. Go ahead. But I would suggest buying a DDR2 800 instead of DDR2 667. If your motherboard supports DD2 1066 memory and you have the money, much better. DDR2 800 is much faster than DDR2 667.