NVIDIA vs ATI Image Quality Comparison (GTX260+ vs HD4850)
 

Factoring everything that has been covered in this article, I tend to prefer nVidia’s image quality overall as I’m a big fan of full scene super-sampling. Visible gains from edge AA tend to rapidly diminish after 4xAA, so to see large improvements during gaming you have to start anti-aliasing other parts of the scene, not just edges. That and after gaming with nVidia’s superior AF since November 2006, I can immediately spot the regression when I game on ATi hardware.

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