I'm currently using the ATI HD 4670
Awesome cheap card, dual 4670's would be even better.
But of course I do like to game with my system too.

Quadro's are crazy expensive and I'm on a budget most of my life.
So anyone considering budget? the new 4600's are great budget cards and can be overclocked.

Take your savings and invest in a Cintiq!!!!

Carrara 7 Pro, Anime Studio Pro 8, Hexagon 2.5, Zbrush 4.6, trueSpace 7.6, and Corel Draw X3. Manga Studio 4EX, Open Canvas 5, WACOM Cintiq 12WX User