How much is it going to cost? Me and a buddy of mine have done extensive real life benchmarks of the XP 1500, 1700, 1800, 2100, 2400, 2700, 3000, and 2400-M. There was not much difference bewteen the 2400, 2700, and 3000 models. I mean, there is only about a 160 mhz between the 2400 and 3000. I say if you can get the 2900 for a decent price, then what the hell right? But if it is going to cost over 100 bucks then I dont think you will see 100 bucks worth of difference. About your bus speed... I ran my XP-M 2400 at 133 FSB and 166 FSB at like, many combinations of multiplier and FSB. From what I saw (based on real time video encoding which is totally CPU dependant) the FSB boost was worth about 50 mhz give or take a few mhz. It was fun testing all these things out but what I learned wasnt so fun: A system based on an athlon XP (even on the bleeding edge of overclocking etc etc) is still slower than the slowest athlon 64 939. Some of the people may argue the point that an XP-M at 2.5 ghz may be equal or a littel faster, but I dont see the point. Considering you have a 6800GT, I would say you will not see noticeable improvement if you got this XP 2900. Keep what you have and put the money towards a new mobo and CPU. Its time for PCI-e anyways if you ask me.