It would be a waste of money venney. The next step up is a Athlon XP3200+ and its not worth the cost to replace a 3000+. Regardless of that, it wont effect your video card. As long as your mobo supports 8X AGP then your doing all you can do with it. Being that you have a MSI board, you should have a little program that came with it called Core Cell. If you dont, you can download it but if you do it will allow you to overclock to a 3200 easly. Thats the fastest 32 bit cpu that you can get in Athlon XP's. (looking for a link to core cell) Im running the same cpu but its OC'ed to a 3200 and runs fine.
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I raised my FSB to 215 but i can actually get about 220 and remain stable. It really depends on your cooling. The MSI site isnt letting me in for some reason but when its up you can get core cell from there.