For specifics, you'll want to contact your card manufacturer, but it's generally a simple enough process. Have the fresh drivers downloaded onto your machine and ready to go, first(this step isn't strictly necessary to complete first, but it'll save your eyes). Then uninstall the drivers as you would another program(Control panel, programs and features). Then restart your computer and it'll boot in horrid VGA mode. Run the downloaded file that you had gotten previously, and it should get your card back up to date.
In programs and features to uninstall the old drivers I only saw the ones I downloaded freshly. When I restarted nothing happened. The problem is still there.