http://www.docsdownloads.com/Tier1/enditall.htmUseful too, I use it before I play a game, closes down all unneeded applications that are hidden on the background.
You can also set it to exclude from closing down certain programs (like vent), etc.
Also works great for vista.
Aside from that, you could also consider overclocking your 6800 a tad. (Your 64 MB is killing it though, you really need 512 these days) But you're better off just getting a new GFX card in the long run, you can get some really cheap ones with great performance. You could also buy another 512 ram cheap.
With these purchases your computer would be as good as new

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