Sony PCG-R505DC - Manual (Page 170)

Troubleshooting the Computer Screen (LCD)
Why did the computer screen (LCD) go blank?
 Your computer screen may go blank if the computer has lost power or is in a power saving mode (Standby or
Hibernate).
 Make sure the computer is plugged into a power source and is on. The power indicator on the computer will
be on if the computer is on.
 Make sure the battery is inserted properly and is charged.
 If the computer is in LCD (Video) Standby mode, press any key to activate the computer screen.
 If the display mode is set to external display (such as TV), press and hold Fn while you press F7 several times.
Why don't my changes appear on the computer screen (LCD)?
You may need to refresh the computer screen. Press the Windows key and press D twice.
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