Run Built-in Diagnostics to determine if the display abnormality rises from the monitor itself or video card and computer malfunctions.
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Run Built-in Diagnostics to determine if the display abnormality rises from the monitor itself or video card and computer malfunctions.

Press and hold Button 5 for four seconds until a menu appears on the screen.

Select to run Built-in Diagnostics

Use the joystick to highlight the Diagnostics option and press it to run Built-in Diagnostics. Observe if the screen has any defects or abnormalities. Toggle the joystick again to go to the next screen. The test is complete when a text screen is arrived. Then, toggle the joystick to exit.

If you do not detect any screen abnormalities, check the video card and computer.