I don't overclock, not worth for me

. MY XP2500+ is running at stock speed, which means that it runs cool even on those hot days of summer after playing FarCry on-line for hours

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What I would do if you want to keep your computer for some more time is add more RAM. 256 MB will improve, 512 is better, but I don't think you need more. I don't know about your hardrive, but that may be another upgrade (and I prefer to replace a drive for a the new which will be faster than to just plug a new drive).