Sony PCG-NVR23 - Manual (Page 72)

Changing the display when connecting an external computer display or projector
When you connect an external display to the VGA (Monitor) port, you can toggle the output between the Liquid Crystal
Display (LCD), the external monitor, or both devices. Press the Fn+F7 key combination to select a display. See Selecting the
Display Mode for more information.
The Fn+F7 key combination may not work if you connect the external display to the computer when the computer is
on. It is recommended that you connect the external display to the computer before you turn the computer on.
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