Ok, let`s start from scratch.
Set a restore point.
Download the latest WHQL drivers from Nvidia.
Download and install the freebie Drivercleaner.
Uninstall all your current and possibly previous video drivers, restart and use Drivercleaner to sweep the system of all remaining driver components.
Restart and install the new drivers you downloaded.
Let us know what happens next, because a lot of video problems are caused by the drivers, either getting corrupted or, most commonly, the uninstall program just fails to do its job properly leaving odd bits behind that mess up any new installation attempted.