Dell P2423D User Manual page 70

No Input Signal
when user controls
are pressed
The picture does
not fill the entire
screen
No video at HDMI/
DisplayPort
│
70 Troubleshooting
No picture, the LED light is
white
The picture cannot fill the
height or width of the screen
When connected to some
dongle/ docking device at
the port, there is no video
when unplugging/plugging
the cable from the notebook
• Check the signal source.
Ensure the computer is
not in Standby Mode by
moving the mouse or
pressing any key on the
keyboard.
• Check if the video cable
is plugged in properly.
Disconnect and reconnect
the video cable if
necessary.
• Reset the computer or
video player.
• Due to different video
formats (aspect ratio) of
DVDs, the monitor may
display in full screen.
• Run the built-in diagnostics.
• Unplug the HDMI/
DisplayPort cable from
dongle/docking device,
then plug the docking
HDMI/DisplayPort cable to
the notebook.