Sony PCG-GR300K - Manual (Page 47)

Hibernate mode
In the Hibernate mode, the state of the system is saved on the hard disk drive and power is turned off. The power indicator
is off in this mode.
To activate Hibernate mode
To activate Hibernate mode, press the key combination Fn+F12.
Note:
The "Save to Disk Manager" screen appears, and then the notebook enters Hibernate mode.
Do not move the notebook until its power indicator turns off.
To return to normal mode
To return to normal mode, turn on the notebook by pressing the power button. The notebook returns to its previous state.
Note:
When returning from Hibernate mode, the system status stored on the hard disk is erased and the notebook starts
normally if you press the power button and hold for more than four seconds.
 Time required to return to normal mode
Standby requires less time than Hibernate to return to normal mode.
 Power consumption
Standby uses more power than Hibernate.
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