or
4. This box also appears during normal system operation, if the video cable becomes disconnected or damaged.
5. Turn Off your monitor and reconnect the video cable; then turn On both your computer and the monitor.
If your monitor screen remains blank after you use the previous procedure, check your video controller and computer, because your monitor is functioning properly.
Built-in Diagnostics
Your monitor has a built-in diagnostic tool that helps you determine if the screen abnormality you are experiencing is an inherent problem with your monitor, or with your computer and video card.
NOTE: You can run the built- in diagnostics only when the video cable is unplugged and the monitor is in self-test mode .
To run the built-in diagnostics:
1. Ensure that the screen is clean (no dust particles on the surface of the screen).
2. Unplug the video cable(s) from the back of the computer or monitor. The monitor then goes into the self-test mode.
3. Press and hold Button 1 and Button 4 on the front panel simultaneously for 2 seconds. A gray screen appears.
4. Carefully inspect the screen for abnormalities.
5. Press Button 4 on the front panel again. The color of the screen changes to red.
6. Inspect the display for any abnormalities.
7. Repeat steps 5 and 6 to inspect the display in green, blue, black, white and text screens.
The test is complete when the white screen appears. To exit, press Button 4 again.
If you do not detect any screen abnormalities upon using the built -in diagnostic tool, the monitor is functioning properly. Check the video card and computer.