5Turn off the computer and monitor, wait 10 to 20 seconds, and disconnect the monitor. Connect the monitor back to the original computer, and then turn them on.
6Turn off nearby fans, lights, lamps, or other electrical devices.
Is the monitor readable?
Yes. One or more of those devices was causing interference. The problem is resolved.
No. Go to step 7.
7Run the VESA/VGA Interface tests in the Dell Diagnostics.
Did any of the tests fail?
Yes. The video controller on the system board may be defective. Contact Dell for technical assistance.
No. Go to step 8.
8Run video diagnostics from the Dell Diagnostics menu.
Did any of the tests fail?
Yes. The video controller on the system board may be defective. Contact Dell for technical assistance.
No. Contact Dell for technical assistance.
Sound and Speaker Problems
Basic Checks:
•Check the diagnostic lights to see if the specific problem is identified.
•If using external speakers:
–Ensure that external audio devices are properly connected to the microphone, speaker/headphone, and
–Ensure that the speaker cable is firmly connected to the computer.
–Test the electrical outlet: verify that the speakers are connected to a working electrical outlet.
–Ensure that the speakers are turned on.