Remember that it's all relative, and there is a certain price/performace curve which in my opinion beyond around about $200 you pay much more for increasingly less performance increases.
This also mostly relates to 3D performance. The matrox cards have the better 2D performace per se, although any card of the past 2 years or more will give you "good" performance up to crazy resolutions (2000 x 2000 anyone?). For Photoshop performance, spend not so much on a graphics card but spend more on a better monitor.
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