Re: Which video card?
You would have to do some Googling to find which games are better with which card. I think in the 4890 vs 275 tests that Nvidia did better in Age of Conan, but ATI did better in the other games (six games, with and without AA on).
Usually there's at most a few FPS difference, but there are some games where the difference is much higher. Again, go to Google. Check out some reviews for the cards, as most use games as benchmarks. You will also find some direct comparisons to help you better judge the results.
My Rig: SABLE
Antec 300 Illusion / Antec EarthWatts EA650 650W / EVGA GTX 760 2GB
AMD FX 8320 x8 Black Edition / Gelid Tranquillo / MSI 970A-G43
Sandisk Ultra Plus 128GB / Samsung 840 120GB / WD Black 750GB / WD Green 1TB / WD Red 3TB
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R.I.P. Danny L. Trotter
... 14 Nov 1945 - 4 Sept 2009