Hi Scott,
What's the actual problem? What happens when you put the card in? Any errors?
One common problem for new graphics cards is that you need to reset the CMOS when you put a new graphics card in (especially if your switching from an ATi card to nVidia). If you look in your motherboard manual then it will show you how to do it in there.
If you don't have the motherboard manual then if you look carefully on the motherboard, there will be in small white text somewhere saying 'CMOS', with 3 pins, and 2 been covered by a piece of plastic, if you switch the pin over to the other side for 20 seconds, then switch it back and turn the computer on, it will reset the CMOS. (Make sure you do this when the computer is off though!).
Hope that helps, I sold the card AS-IS, but it worked perfectly fine when I had it, so no offense but it's a problem on your side - but I'm more than happy to help guide you through to sorting the problem out.
Kind regards,
Adrian.