Sounds like it could be a driver
issue. If its something that recently happened you can go into your device manager find the video card and roll back the driver.
Select start orb
Right click on computer
On the left side of computer manager you should see the option device manager. Select device manager.
Click the arrow on display adapters.
Your video card should now be displayed.
Right click on the video card name.
Select the driver tab.
Select roll back driver.
(If that option is not available check the manufactures website for new drivers
.) Or give us your pc manufacture or video card manufactured and we can help you find drivers.