Windows 7 Best Component Upgrade for Gaming: GTX 460 SLI or Alternatives?

Not really much to beast that up to be honest, aside from a faster SSD drive or a higher GPU, thats a fairly high spec for most games, although you might have to upgrade the PSU to go down the SLI route. Also worth mentioning what resolution you play at, as that would indicate if the GPU needed to be a higher model or one with 1.5gb or 2gb ram on it. The GPU's ram only really becomes an issue beyond about 1680x1050, up to then any 1gb is perfectly fine, by the time you get to 1080p and above as the newer games max out the textures, 1gb will start to be the minimum amount to have rather than the perfect amount. It is also woth pointing out that while SLI/Crossfire methods are a cheaper way to jump up the 3d power of the PC, you don't get 2x the power for having 2 cards, typically you will expect anything from 1.5x to 1.8x the horsepower depending on driver support and brand, personally I always favour a 1 card solution of higher model rather than SLI etc as often uses less power which offsets the higher purchase price over time.