If you put a limit of $300 on your graphics subsystem, you are most likely shopping for an HD6950 or possibly a heavily overclocked GTX 560 Ti or a discounted GTX570.  [H]ard|OCP tested out a different choice, two of MSI’s N550GTX-Ti Cyclone II card in SLI, which can also be had for under $300.   The testing did not go so well for NVIDIA’s less powerful card, the HD6950 won in almost every test and consumed less energy doing so.  There were certain situations in which they would recommend running the cards in SLI, specifically when you already own a GTX 550 or other lower powered NVIDIA card and don’t plan on playing at resolutions above 1920×1200.  Only then would this upgrade make sense.

"Packing a GeForce GTX 550 Ti GPU each, we have a pair of N550GTX-Ti Cyclone II video cards that we are going to evaluate against a Radeon HD 6950, GeForce GTX 570 and even an overclocked GeForce GTX 560 Ti. At a total cost of only $260 we will find out if this dual-GTX 550 Ti action has what it takes to compete. "

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