Update, I just found that GT 650 will be available,
but I prefer the bigger screen with GTX 675
You can always hack the raytracer_supported_cards.txt file - on your own head, of course. Beyond that I wouldn't let my buying decision be driven by a half-baked feature like the Raytrace 3D. Seriously. That stuff is gonna change again in CS7 no doubt (hopefully for the better) and locking yourself into a specific hardware just to be compatible now may then prove disadvantageous (though arguably those nVidia cards will still somehow be put to use then). Honest, straight up answer: Buy whatever you need, learn a serious program on the side and/or invest some money in some 3D-ish plug-ins should the raytrace stuff not work on your hardware or you generalyl end up frustrated because it's so limited.
Your subject line confuses me. Are you sure that you mean to be asking about OpenGL, not CUDA?
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