Power management is a feature of some electrical appliances, especially copiers and computer peripherals such as monitors and printers, that turns off the power or switches the system to a low-power state after a period of inactivity. APM has been superseded by ACPI. All recent computers have ACPI support.

Hibernation

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''Main article: Hibernate_(OS_feature)

When computer system hibernates it dumps the entire contents of the RAM to disk and powers down the entire machine. On startup it quickly reloads the data. It allows the system to be completely powered off while in hibernate mode. This requires a file the size of the installed RAM to be placed in the system's root directory, using up space even when not in hibernate mode. Hibernate mode is enabled by default in some versions of Windows and can be disabled in order to recover this disk space.

See also

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• Advanced Power Management (APM)
• Advanced Configuration and Power Interface (ACPI)
• VESA Display Power Management Signaling (DPMS)
• Energy Star
• Hibernate
• Green computing and Green energy

External links

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• Energy Consumption Calculator

Energy conservation