I would steer clear of ATI gamecards, they are rubbish (not the hardware more the driversets)

The difference between a Quadro and a GForce used to be about viewport performance(more, bigger and better textures faster replay on animations in the viewport), but somehow Maya feels sluggish to me since 2008 and i have a quadro 4600 with a dual quad core machine.

I now Maya doesn't use multiple cores for better performance or makes use of GPU acceleration (Real time HDRI, multicore app, gpu acceleration etc) i agree with G-ster and you get a geforce.

I hope that maya 2010 just has the forementioned improvements so i can justify my Workstation