Screen tearing mainly occurs when the frame rate exceeds your monitor's refresh rate. When this happens, parts of two frames are drawn to the display at once, creating a "tear" between the two frames in the form a horizontal line or lines across your screen.

The simplest way to reduce screen tearing is to enable V-Sync from either in game or from the Nvidia Control Panel. This sets your frame rate to your monitor's refresh rate, greatly reducing the amount of tearing you experience. The main disadvantage of screen tearing occurs when your frame rate drops below the refresh rate. V-Sync will force your frame rate to a number of frames evenly divisible by the refresh rate. For example, on a 60Hz display with V-Sync on, dropping below 60 FPS will force your frame rate to 30 FPS (60Hz/2=30 FPS).

To prevent this frame rate drop but still retain the advantages of V-Sync, Nvidia has what is called Adaptive V-Sync. It functions the same as V-Sync, but when frame rates drop below the refresh rate of the monitor, Adaptive -Sync turns off to allow a variable frame rate.