The Quicksilver uses a 133mhz bus, the Sawtooth only uses a 100mhz one. The Quicksilver 800 CPU would have a multiplier of 6, so it would only run at 600mhz on a Sawtooth, if it worked at all. You would also need to be able to run an additional power line to the Quicksilver CPU because it normally draws power from one of the posts it rests on in the Quicksilver case which isn't in the earlier models. Sometimes you can find overclocked CPU's on ebay if you think you can trust that sort of thing. If you really need a faster CPU, though, and your motherboard supports it, go for a dual 450 or 500. They are dirt cheap. Otherwise you can save for a faster aftermarket CPU upgrade, which might be a good idea to do since they seem to be drying up.