Save for the readily available GeForce GTX 670 graphics card, procuring a Kepler-based videocard from Nvidia
is no easy task. If you do happen to get your mitts on one, however, you'll want to hop over to Nvidia's driver download site and grab the latest drivers, version 301.42, which happen to be the first WHQL-certified unified drivers from Nvidia's R300 family.
According to Nvidia, the new drivers pack "some really nice performance increases in top games," including up to 23 percent better framerates in Just Cause 2 with two or more GeForce GTX 570/580 cards in SLI, up to 21 percent in Skyrim (under the same conditions), and several other double-digit percentage performance bumps.
From a support standpoint, the new drivers play nice with Nvidia's GeForce GTX 690, 680, and 670 GPUs, as well as the entire GT 600 Series. There are new Surround Sound capabilities packed into the new driver package, new and/or updated SLI profiles, more robust 3D Vision profiles, and other goodies.
You can download the new drivers here