Power Request Types: What's the difference between Display, System, Awaymode. (powercfg)

Solution 1:

These power request types correspond to the POWER_REQUEST_TYPE enumeration in the Windows API.

This answer is based on the following pages from the Windows API:

  • POWER_REQUEST_TYPE enumeration

  • PowerSetRequest function

DISPLAY power request type (PowerRequestDisplayRequired)

This request request has the following effects:

  • After a period of user inactivity, the session display stays on and will not automatically turn off. If the display is already turned off, the power request turns the display on.

  • A screensaver will not automatically start after a period of user inactivity. If a screensaver is already running, the power request stops the screensaver.

  • The session will not be automatically locked after a period of user inactivity. If the session is already locked when the driver sends the power request, the session remains locked.

SYSTEM power request type (PowerRequestSystemRequired)

This request prevents the computer from automatically entering sleep mode after a period of user inactivity.

This request type is not honored on systems capable of connected standby. Applications should use PowerRequestExecutionRequired requests instead.

AWAYMODE power request type (PowerRequestAwayModeRequired)

The system enters away mode instead of sleep in response to explicit action by the user. In away mode, the system continues to run but turns off audio and video to give the appearance of sleep.

While a PowerRequestAwayModeRequired power request is in effect, if the user tries to put the computer into sleep mode (for example, by clicking Start and then clicking Sleep), the power manager turns off audio and video so that the computer appears to be in sleep mode, but the computer continues to run.

EXECUTION power request type (PowerRequestExecutionRequired)

The calling process continues to run instead of being suspended or terminated by process lifetime management mechanisms. When and how long the process is allowed to run depends on the operating system and power policy settings.

On systems not capable of connected standby, an active PowerRequestExecutionRequired request implies PowerRequestSystemRequired.

Note: PowerRequestExecutionRequired is supported starting with Windows 8 and Windows Server 2012.