15th July 2010, 7:12 PM
Really, almost anything is an upgrade to what you have now, so it all depends on how much you're willing to spend and how long you'd like it to last considering the fast pace of PC hardware. Generally speaking though, a good powerful card can be anywhere from $100 to, well, the absurdly expensive cutting edge ones, with the best bang for your buck usually lingering in the $150-$200 range.
The Earthworker Race has ended. Everybody wins.