I have NEVER done this. Here's why. Not only must the driver file be backed up, but any registry keys and more. I've yet to find a software that could do this trick.
What I have done is to keep the driver install software ready for use.
Bob
Where is the best place to back drivers up to prior to downloading the new ones? Once backedup, should the originals be deleted out of their original folder?
How do you back them up? (ie. just copy or actually use a backup program). Thanx all.

Chowhound
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