I second Trouble, probably a bad driver. If you have done anything with BIOS settings, I would recommend default settings. And, sometimes it helps to solve the problem by using the original drivers that came with the video card. Update after update can cause trouble, quite often older drivers work better. To unistall new ones, and go back to the original, may help. Afterwards, you can update, step by step.
If you have a grasp of when the problem started, you can try a Recovery: Control Panel\All Control Panel Items\Recovery --- pick a point earlier, to be on the safe side. You will see "Recommended restore" and "Choose a different restore point". Choosing the latter, you will see "Show more restore points" and you'll have practically...