I know I am really late to the party for this thread, but I wanted to make a point just in case other people are searching for info on video cards for solidworks or other professional applications.
One point is that there is a bigger difference between professional video cards and gaming cards that just support. Professional cards have certain features enabled that gaming cards do not. Because the pro cards have these extra features enabled, they have a much higher performance in apps like Solidworks, Pro/E, etc.
Here is a good example:
http://www.tomshardware.com/reviews/amd-firepro-v8700,2154-10.html
That is a professional CAD type benchmark done using an ATI 4870, and it's professional counterpart, the FirePro V8700. The cards have the same GPU, but they have different drivers and perform very differently in professional apps. The FirePro card is 3 or 4 times faster across the board, and I bet more accurate in what gets displayed on the screen too. No, you can't simply install the pro drivers for the 4870, it won't work that way.
So a weak pro card can smoke a high end gaming card in pro apps. I have seen benchmarks showing this. I can't find it now, but I remember one test where an 8800gt got destroyed by the quadro equivalient of an 8600GT in Solidworks, and the quadro equivalent had slower memory than a real 8600GT.
Also note that you don't get Realview in Solidworks unless you have a professional card.
And no, the pro cards are not faster at games because of their unlocked professional capabilities. In fact they are slower at games.
So just understand the pro cards have big performance differences, are more accurate for rendering, and you get support.
But if you are on a tight budget and can't afford one, lots of people use gaming cards and are productive.
I just want people to be more aware before spending money.