KOOL, is that a name brand computer? I mean a dell, gateway etc or one that you build yourself? reason I ask is if you build it yourself you can upgrade your mobo/ram/cpu and keep everything else. if it is a name brand then most likely the only thing you can reuse is your hd and cd rom and maybe your copy of windows.
If I was you I would order the video card and see how it plays with what you have. I had an e8400 cpu oc like crazy and was able to play the game at full settings with shadows at 2048 using an evga 465 video card. the e8500 is a very good processor and not as low end as they make it sound. just make sure the card will fit in your case.
but to make sure post more info about your system specially who build it

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semp