To automatically put your computer into hibernation
You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings may also prevent you from completing this procedure.
Open Power Options in Control Panel.
Click the Hibernate tab, select the Enable hibernate support check box, and then click Apply.
If the Hibernate tab is unavailable, your computer does not support this feature.
Click the APM tab, click Enable Advanced Power Management support, and then click Apply.
The APM tab is unavailable on ACPI-compliant computers. ACPI automatically enables Advanced Power Management, which disables the APM tab.
Click the Power Schemes tab, and then select a time period in System hibernates. Your computer hibernates after it has been idle for the specified amount of time.
To open Power Options, click Start, click Control Panel, click Performance and Maintenance, and then click Power Options.
When you put your computer into hibernation, everything in computer memory is saved on your hard disk, and your computer is switched off. When you turn the computer back on, all programs and documents that were open when you turned the computer off are restored on the desktop.
To put your computer into hibernation, you must have a computer that is set up by the manufacturer to support this option.
Using Power Options in Control Panel, you can adjust any power management option that your computer's unique hardware configuration supports. Because these options may vary widely from computer to computer, the options described may differ from what you see. Power Options automatically detects what is available on your computer and shows you only the options that you can control.