First you'll need a 3D compatible graphics card. In the high end, you can go with the GTX 580 or 570. If you want the older generation, the 480, 470 or 460 should suffice for one TV at a resolution of 1080p. Then, you'll need Nvidia 3D Vision Kit.
If you want to do some heavy 3D gaming, then I'd suggest getting two 500 serie cards in SLI, the scaling is almost 100%.