the geforce series of nvidia and the radeon from ati are specifically designed to play games. the are not designed for high end cg work. if you want that, nvidia has the quadro. these cards are not good for games. heres why
a gaming card renders each scene with errors. ie, one pixel is one shade different than the others on a plain background. most people never notice this, and so it doesnt matter. people using lightwave, maya, max, any high end stuff for high end work (pixar or any other cg company that can afford it) will have a high end graphics card that is looking for quality, not quantity. it will render a scene with no errors at lets say 40fps. but a gaming card will do 60fps with its errors. matrox is a high end rendering card but may not be that fast
for example: which is better for gaming. which one for 3d modeling, which one for etc.
any card will do you good for blendering because rendering is cpu dependant. gaming, go with a 7800gt or gtx because they are insanly fast.