Ok, thanks everyone. I was looking at Dell, and it looked like my processor speed was still good, but maybe there are other things I didn't consider. I was hoping that a new graphics card would really help, but I had a feeling I would need to get a new system. I will take a look at the HD4670 though.
I just realized you said it would be all my PSU would be able to take, not my processor... so it doesn't matter if my processor is still decent.
Thanks again everyone.