Removing and Wiping Drivers Guide @ OCC
 

When you open Driver Fusion you will be greeted by the 'Driver Inspection' page, which lists the different drivers you may want it to scan for. Just click on the items in the list in order to select them, and clicking on multiple items will select those multiple items. Pressing the 'Analyze' button will have the program start searching for what remains of the drivers you told it to look for, and what it finds will be listed for you to inspect. It finds files, folders, and registry entries, each of which you can choose to leave on your computer by clicking the appropriate checkbox on the side of the list. It may be a good idea to check this list before pressing the 'Delete' button because it may find something you do not want deleted, such as files that have been extracted for when you install new drivers. You can see I have unchecked the "C:\NVIDIA" directory in the screenshot, and I did so specifically for that reason.

http://www.overclockersclub.com/guides/wiping_drivers/