I have a first generation mac pro. a dual core 2 X 2.66 with 8 GB ram, recently I am working with Mac version of Auto-Cad,My computer is too lazy with CAD, I am not sure this is the software problem or my computer. I think my graphic (NVIDIA GeForce 8800 GT) card is not fast enough for graphic processing. I would like to buy a better graphic card, anybody knows about type and price of a good graphic card able to work in hard situation like 3D and rendering jobs?