Thanks. Here's a list of things to try. Try them all:
* Remove old drivers; install latest ones.
> Go into Add/Remove Programs and uninstall all your video card driver and software
> For good measure, use this program to remove any extra drivers:
http://www.guru3d.com/files_details/display_driver_uninstaller_download.html
> Run that program on both NVIDIA and AMD
> Afterwards, go to AMD, Nvidia, or Intel and download and install the latest drivers for your video card.
* Test again with a different monitor AND a different cable on the same computer; it is possible that the monitor or cable could have developed a defect in just the last few months.
* Does this issue happen in ALL programs or just your web browser? If it's just the browser, then delete it and re-download it again... or better yet, use a different one like maybe Firefox.