Dell PP23LA Owner's Manual page 34

If the video resolution setting is higher than that supported by the display, the computer enters pan
mode. In pan mode, the entire screen cannot be displayed at one time. For example, the taskbar that
usually appears at the bottom of the desktop may no longer be visible. To view the rest of the screen, use
the touch pad or track stick to pan up, down, left, and right.
NOTICE:
You can damage an external monitor by using an unsupported refresh rate. Before adjusting the refresh
rate on an external monitor, see the user's guide for the monitor.
34
Using the Display
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