any pci-e 2.0 card will work fine with it as there backward compatable!
just check what the ampage on your +12V rail on your psu is and i or anyone else would be able to make an actual suggestion?
without the ampage on your +12v its hard to say as we have no idea what psu you have!
also what are you thinking of using the graphics card for (watching videos, playing games or just general use)?