Based on your description, this issue could have been caused by a windows update.
I recommend you uninstalling the graphics driver and installing the latest one from your Computer Manufacture. In the case the driver from the Computer Manufacture is not working you can try our generic driver.
Here you have the download link:
If during the installation of the driver you find problems, try the steps mentioned here:
Another step you can try is running a windows system restore to a previous point when the computer was working fine. This could do the trick.