Sony PCG-GR300K VAIO User Manual page 78

To select a display
When you connect an external display to the Monitor port, you can toggle the output between the Liquid Crystal Display
(LCD), the external monitor, or both devices.
Use the Fn+F7 keys to select a display. See also 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:
Connect the cable before you turn on the notebook, otherwise Fn + F7 will not work.
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