Sony PCG-GRT170 - Manual (Page 136)

Why doesn't my computer enter Hibernate mode?
You may first need to enable Hibernate mode. Follow these steps:
1. Click Start on the Windows ® taskbar, and click Control Panel.
2. Click Performance and Maintenance, and click Power Options. The Power Options Properties window
appears.
3. Select the Hibernate tab.
4. Click to check the box next to Enable hibernation.
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