Mobile Computing in Windows Vista : Managing Notebook Power

Monitoring Your Notebook with the Windows Mobility Center

The Mobile PC Control Panel offers links to a broad range of notebook features. A more targeted approach is the new Vista Windows Mobility Center, which you start by clicking the Windows Mobility Center link in the Mobile PC Control Panel. Figure 2 shows the Windows Mobility Center window that appears. (Note that you only see the full Mobility Center in the Business, Enterprise, and Ultimate editions of Vista.)

Figure 2. The new Mobility Center offers a selection of information and controls for notebook-related features.

The Mobility Center offers information on eight key notebook areas, as well as controls to adjust these features:

• Brightness— The current brightness setting of your notebook screen (if your machine supports this features). Use the slider to adjust the brightness.

• Volume— The current notebook speaker volume. Use the slider to adjust the volume or click Mute to toggle sound off and on.

• Battery Status— The current charge level of the notebook battery. Use the drop-down list to select one of three power plans: Balanced, Power Saver, or High Performance .

• Wireless Network— The wireless connection status (Connected or Disconnected), and the signal strength, if connected.

• Screen Orientation— The current orientation of the Tablet PC screen. Click Rotate Screen to rotate the screen by 90° counterclockwise.
  

• External Display— The current status of the external monitor connected to your notebook or docking station. Click Connect Display to open the Display Settings dialog box and work with the second monitor.

• Sync Center— The current synchronization status of your offline files. Click the Sync button to synchronize your notebook’s offline files.

• Presentation Settings— The current status of your presentation settings. Click Turn On to activate your presentation settings.

Note, too, that Microsoft is giving PC manufacturers access to the Mobility Center, so we’ll likely see the Mobility Center window customized with features that are specific to particular notebooks.

Managing Notebook Power

If you must run your notebook without AC (on an airplane, for example), maximizing battery life is crucial. Like most of its predecessors, Windows Vista supports various power schemes—Vista calls them power plans—that specify different time intervals for when the notebook is plugged in and when it’s on batteries. However, it’s equally important to monitor the current state of the battery to avoid a shutdown while you’re working.

Monitoring Battery Life

To help you monitor battery life, Windows Vista displays the Power icon in the notification area. When you’re running on AC power, the Power icon also includes a plug, as shown in Figure 3. When you’re on batteries, the Power icon is completely green and displays without the plug, as shown in Figure 4. As your notebook uses up battery power, the amount of green decreases accordingly.

Figure 3. On AC power, the Power icon includes a plug.

Figure 4. On batteries, the amount of green in the Power icon tells you how much battery power is left.

To see the exact level of battery power remaining, you have three choices:

• Open the Mobility Center (as described in the previous section) and examine the Battery Status display.

• Hover the mouse pointer over the Power icon. After a second or two, Windows Vista displays a fly-out that tells you the approximate time left on battery power and percentage of battery life remaining (see Figure 5).

  Figure 5. Hover the mouse pointer over the Power icon to see this fly-out.

  

• Click the Power icon. Windows Vista displays a larger fly-out, shown in Figure 6, that not only shows you the approximate time left on battery power and percentage of battery life remaining, but also enables you to change the current power plan (Balanced, Power Saver, or High Performance).

  Figure 6. Click the Power icon to see this fly-out.

  

Specifying a Power Plan

Windows Vista shuts down some system components in an effort to keep your battery running longer. This is controlled by your current power plan, a power-management configuration that specifies which components shut down and when Windows Vista does so. Windows Vista has three power plans:

• Power Saver— Devices such as the screen and hard disk are powered down after a short idle interval. For example, on battery power, Windows Vista turns off the notebook screen after 3 minutes and the hard disk after 5 minutes.

• High Performance— Devices are powered down only after a longer idle interval, which improves performance because you’re less likely to have to wait for them to start up again. For example, on battery power, Windows Vista turns off the notebook screen and hard disk after 20 minutes.

• Balanced— This is the middle road (more or less) between the Power Saver and High Performance plans. For example, on battery power, Windows Vista turns off the notebook screen after 5 minutes and the hard disk after 10 minutes.

The default power plan is Balanced, but Windows Vista gives you three methods to change it:

• Using the Mobility Center— In the Battery Status section, use the drop-down list to select a power plan.

• Using the Power icon— Click the Power icon to see the banner shown in Figure 9.6, and then click the power plan you prefer.

• Using the Power Options window— Click the Power icon and then click More Power Options (or select Start, Control Panel, Mobile PC, Power Options) to display the Power Options window shown in Figure 7; then click a power plan option.

Figure 7. Double-click the Power icon to display the Power Options window.

Creating a Custom Power Plan

Vista’s preset power plans are probably fine for most uses, but you might want to tweak some plan characteristics. For example, you might want a plan that never turns off the hard disk or that waits longer before turning off the display when the notebook is on AC power. For these and other custom plan settings, Vista gives you two choices: creating your own plan and customizing an existing plan.

Creating Your Own Power Plan

You can set up a new plan that specifies the intervals when Vista turns off the display and puts the computer to sleep both while on battery power and while plugged in. Here are the steps to follow:

1.	In the Power Options window, click Create a Power Plan. Vista displays the Create a Power Plan window.
2.	Click the built-in power plan that you want to use as a starting point. Caution The custom plan you create becomes one of Vista’s default plans, meaning it appears in the fly-out when you click the Power icon and in the plan list in the Mobility Center. However, Vista replaces whatever built-in plan you use to get started on your custom plan. (You can still activate the original built-in plan using the Power Options window.) Therefore, don’t base a new custom plan off an existing plan that you activate frequently.
3.	Type a Plan Name and click Next. Vista displays the Edit Plan Settings window, shown in Figure 8. Figure 8. Use the Edit Plan Settings window to specify the sleep and display settings for your custom power plan.
4.	In both the On Battery and Plugged In columns, select an idle interval after which Vista will turn off the display and put the computer to sleep.
5.	Click Create. Vista creates your custom power plan.

Customizing an Existing Power Plan

Just because you saw in the previous section that Windows Vista gave only you two measly power settings—turning off the display and putting the computer to sleep—for your custom plan, that doesn’t mean that’s the extent of Vista’s power options, far from it. You can customize any plan (including a custom plan) with a large number of settings. To work with these settings, follow these steps:

1.	In the Power Options window, click the Change Plan Settings link under the plan you want to customize. You see the Edit Plan Settings window (shown in Figure 8).
2.	Specify your idle intervals for Turn Off the Display and Put the Computer to Sleep.
3.	Click the Change Advanced Power Settings link. This displays the Advanced Settings tab, shown in Figure 9, which offers a wide range of power-management settings. Figure 9. Customizing an existing power plan gives you a much wider range of power-management options.
4.	Use the branches in the Advanced Settings tab to set your power management options. Tip To see all the available settings, click the Change Settings That Are Currently Unavailable link, and then enter your UAC credentials.
5.	Click OK.
6.	Click Save Changes. Vista updates the power plan.

Configuring Your Notebook’s Power Buttons

Most newer notebooks enable you to configure three “power buttons”: closing the lid, using the on/off button, and using the sleep button. When you activate these buttons, they put your system into sleep mode, hibernate mode, or turn it off altogether. On some notebooks, there isn’t a separate sleep button; you simply tap the on/off button quickly.

To configure these buttons for power management in Vista, follow these steps:

1.	In the Power Options window, click the Choose What the Power Buttons Do link to see the System Settings window, shown in Figure 10. Use the lists to configure the power button, sleep button, and lid switch for battery power and AC power. Figure 10. Use this window to configure what Vista does when you press the power button, the sleep button, or close the notebook lid.
2.	Use the lists to configure the power button, sleep button, and lid switch for battery power and AC power. Tip By default, Vista disables the options in the Password Protection on Wakeup group. This means that you always have to enter your user account password when Vista wakes from Sleep or Hibernate mode. If you prefer not to enter your password each time, you can enable these options by clicking the Change Settings That Are Currently Unavailable link, and then entering your UAC credentials. Once you’ve done that, you can click the Don’t Require a Password option.
3.	Click Save Changes.