Symptoms
Dell monitor is defective/non-functional.
Cause
Various
Resolution
Perform a Dell monitor self test.
To find if your Dell monitor is still under warranty, you can call Dell at 800-234-1490 (Dell Technical Support for Education). You will need the Service Tag of your PC which is located on the back of your processor unit for older PCs. For newer PCs, look for the Service Tag on the side panel. If your PC and monitor is still under warranty, Dell will ship you a replacement monitor in box with prepaid freight bill to ship the defective part back to Dell.
Outcome
You will be able to determine how to acquire a replacement Dell monitor.