Controlling Your Desktop’s Power Management

Contents

9.1. Using the Battery Monitor Widget
9.2. Saving Power by Using Profiles
9.3. Configuring Power Management

In KDE 4, you can control power management functions supported by your system with just a few clicks on the desktop. You can choose between various power management profiles to match the tasks your system is facing. The Personal Settings hold a Power Management category, allowing you to configure detailed settings as described in Section 9.3, “Configuring Power Management”.

Apart from power profiles that can be applied while you are interacting with your computer, there are also power saving functions (suspend modes) you can use instead of shutting down the computer completely during breaks.

Using the Battery Monitor Widget

If you are using mobile computers like a laptop, a widget in your panel displays the battery status and gives you access to power management functions. If the Battery Monitor widget is not displayed in your panel by default, add it manually. For more information, refer to Procedure 3.2, “Adding Widgets to the Desktop”.

The widget allows you control the screen brightness when your system is running on battery power, to switch to a different power profile, or to trigger your system to enter a suspend mode. Click the panel icon to open the widget.

Figure 9.1. Battery Monitor Widget

Battery Monitor Widget

Which suspend modes and power profiles are available depends on the power management abilities of your system and the profiles defined in the Personal Settings.

The following suspend modes are widely available:

Sleep (Suspend to RAM)

Pauses your computer without logging you out. All your data and the session data is saved to RAM. Bringing the system up again is faster than restoring a session from disk.

Hibernate (Suspend to Disk)

Pauses your computer without logging you out. All your data and the session data is saved to disk before the system is laid to rest. It is thus protected against data loss should you lose power in the meantime. Waking the system up again is much faster than with a fresh boot.

To manually suspend your computer, use the buttons in the widget or the suspend options on logging out (see Section 1.3, “Leaving Your System”). If supported by the system and configured accordingly, pressing sleep buttons on your machine or keyboard will also suspend your machine.

You can configure your system to automatically switch to suspend mode after certain events like closing the lid (if you are using a laptop) or after a period of that time that the system has been idle. Refer to Section 9.3, “Configuring Power Management” for more information.