Longer battery life

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This page refers to a feature introduced in XO Software Release 8.2.0 (AKA build 767). See the 8.2.0 release notes here

Contents

Power management

The XO has several power saving modes.

Default power management

With no checkboxes selected in the power save control panel the XO will save power in the following ways:

  • The XO screen will go blank if you do not touch the keyboard or touchpad for 20 minutes. When this happens, touching the keyboard or touchpad will wake up the display.
  • If you close the lid or press the power button briefly then the XO will go into suspend mode. In suspend mode the CPU stops running programs. The screen goes black. The wireless will continue operating if you are connected in a Mesh but it will shut down if you are connected to an access point. Awaken the machine by pressing the power button again, or by opening the lid.

Important note: the following functionality is not a supported feature yet. You may experience unexpected behavior after checking the Automatic Power Management or Extreme Power Management, but you can help us try it out and find issues.

Automatic power management

If you select the Automatic power management check box in the Power panel under the Graphical sugar control panel, the XO also saves power in the following ways:

  • The screen dims and the XO goes in to "idle suspend" mode if you don't touch the keyboard or touchpad for one minute and the CPU is idle. In "idle suspend" mode the CPU will stop running programs, while leaving the display on (but dimmed).
  • In "idle suspend" mode, if you touch the keyboard or touchpad, the XO screen will wake up from dimmed mode and the CPU will restart.
  • When the XO enters "idle suspend" mode it powers down all USB ports including any USB to Ethernet connectors. Because not all devices can recover from this automatically, you may need to reconnect those external devices or reboot the XO to enable them again. As an exception to this guideline, USB storage devices ("USB sticks") do work correctly after a suspend and resume but they should not be removed while the system is suspended.

If the laptop is in "idle suspend" mode when the lid is closed, the display will remain active. To fully suspend the laptop, the lid should be opened, and closed again, or the power button should be pressed before closing the lid.

Extreme power management

If you select the Extreme power management check box in the Power panel under the Graphical sugar control panel, the XO saves power in the following ways:

  • The wireless radio is shut off immediately and for the duration that Extreme Power Management is activated.

No wireless networking is possible when in this mode.

For more detail on the intended design of power saving modes, see Suspend and resume.

See also

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