Sony PCG-GRX580P - Manual (Page 85)

To change 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.
Use the Fn+F7 key combination to select the display you want. See Selecting the Display Mode for more information.
To Press Result
Switch to an external display Fn+F7 Toggles between the LCD, the external display connected to the Monitor port, or both
the LCD and external display.
Note:
(On selected models) Connect the external display to the notebook or port replicator before you turn on the unit, otherwise
the Fn+F7 key combination will not work.
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