I would try some of the newer drivers from the nVidia site. There have been seven newer releases of the new Quadro series driver since the SW approved version.
If you've been playing around with different drivers recently, you may need to use a clean-up utilty like http://www.guru3d.com/category/driversweeper/ or http://www.afterdawn.com/software/security/system_cleanup/driver_cleaner_pro.cfm
I will give that a try. I have had a few video cards in my system. Although all have been the new Quadro's, with the same driver.
Interesting thing is my home system doesn't suffer from this and it has the Quadro 4000 in it as well.
I am thinking I may need to dump my SW profile in the system registry and start over.
I don't recall ever seeing that. My current card is an AMD but others here are FX570's for the most part.