Answer

Please refer to the attached PDF file for troubleshooting if you encounter crash, black screen and TDR on Overwatch.

Overwatch is a heavily threaded game with fairly complex rendering features. It will use as much of your computer’s CPU and GPU resources as you allow. In the worst cases it can cause your game crash, black screen and TDR (Timeout Detection and Recovery) of your graphics driver.

MSI suggest you try to enabled LIMIT FPS and VSYNC in the video options.

Reference