The self-test (integrated diagnostic tool) helps you determine if any screen abnormality you experience is an inherent problem with: (For example: Your monitor, video cable, video card, driver, or computer.)
Steps for running the self-test:
Disconnect all video cables from the monitor and turn off your monitor.
Turn on the monitor.
When the Dell logo disappears and the screen shows "No signal," press buttons 2 + 3 + 5 (Figure 1) on the monitor simultaneously.
The monitor enters the self-test screen.
Carefully inspect the screen for abnormalities as the display turns to red, green, blue, black, and white automatically.
Press button 5 to exit the self-test screen.
If you do not detect any screen abnormalities while using the self-test tool, the monitor is functioning properly. Check your video cable, video card, drivers, and computer.
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