Diagnosis
The monitor is powered but not receiving a valid video signal from your source. The blue power LED confirms this state.
How to Fix It
Power cycle the monitor and source. Turn the monitor off via its power button. Unplug the monitor from AC power for 60 seconds. While it's unplugged, restart your PC or gaming console. Reconnect power to the monitor and turn it on. Verify the correct input source is selected using the OSD sidekick or the monitor's physical buttons.
If That Didn't Work
Test with a different DisplayPort or HDMI cable. Ensure the cable is fully seated at both ends. Try connecting to a different source to isolate the monitor as the problem.
Heads Up
If using the KVM feature, ensure the correct USB-C or USB-B upstream cable is connected to the PC you are trying to display. The KVM will only pass video from the PC connected to its upstream port.