Manage Your Tablet PC Battery Power
Published: November 7, 2002
On This Page
Summary
Microsoft Windows XP Tablet PC Edition supports the industry standard power management technology known as the Advanced Configuration and Power Interface (ACPI), which enables the operating system to control power to your computer and peripheral devices. All Tablet PC models are ACPI compliant.
In addition to the power management features built into your operating system, a number of power management features are under your control. To get the most out of your battery, you need to know what those user-controllable features are and which settings are optimal for your mobile computing environment.
How you manage your power consumption depends on several factors:
| • | Length of time you are away from an AC power supply |
| • | Battery performance of your particular Tablet PC model |
| • | Power demands you place on your computer while away from AC power |
The illustration to the left offers a continuum of power management options for you to consider as you unplug your Tablet PC, or any portable computer, and work on the go. Each of the power management options is described in this article.
This article also offers suggestions on how to use these options to extend the life of your Tablet PC battery while you are away from your desk. Topics covered include:
| • | Charging your battery |
| • | Monitoring your battery |
| • | Adjusting screen brightness |
| • | Turning off power-consuming components like wireless network connections |
| • | Using power schemes |
| • | Using standby and hibernation features |
Note: Power options may vary from computer to computer. The options described here may differ from what you have available on your Tablet PC. Power Options in the Control Panel—where you manage most of your power options—automatically detects what is available on your computer and shows you only the options you can control. Consult your hardware manufacturer's documentation for more information specific to your computer.
Charging Your Battery
Charge your battery whenever you are at your workstation or AC power is available. Leaving your workstation with a fully charged battery is your first step in maximizing your mobility.
Monitoring Your Battery
You can easily monitor your battery to see how much power you have available while you are working away from your desk.
To check your battery power if you are running on battery power
Double-tap the 
battery icon in the notification area of the Windows taskbar.
Note: The battery icon appears only when your Tablet PC is running on battery power.
You can monitor your battery as it charges to see when it is fully charged.
To check your battery power if you are running on AC power and charging your battery
1. | On the taskbar, tap the Start button, and then tap Control Panel. |
2. | Tap Performance and Maintenance, and then tap Power Options. |
3. | Tap the Power Meter tab. |
4. | Total battery power remaining is shown under Power status. Note: On the Advanced tab you can select the Always show icon on the taskbar check box if you want to see a power status icon in the notification area at all times. Use a right-click equivalent on the power status icon to open the Power Meter. |
You can set Power Options to warn you when the level of battery power falls below the levels you have defined as low and critical. You can change the battery level at which the alarm or message is activated.
To set a warning alarm that is activated when your battery is low
1. | On the taskbar, tap the Start button, and then tap Control Panel. |
2. | Tap Performance and Maintenance, and then tap Power Options. |
3. | Tap the Alarms tab. |
4. | Under Low battery alarm and Critical battery alarm, specify the settings that you want by moving the slider. |
5. | Tap Alarm Action to select the type of alarm notification and resulting action you want. |
Adjusting Screen Brightness
The brightness of your Tablet PC screen is often the number one consumer of power, so you can conserve battery power by turning down the screen brightness on your Tablet PC. By default, your screen will dim when you unplug from AC power. How much it dims depends on the particular settings for your model. You can adjust the default settings for both AC and DC power. When you are plugged into AC power, your screen can be at its brightest, and when you unplug your computer, your screen will automatically dim to conserve power.
To adjust screen brightness
1. | On the taskbar, tap the Start button, and then tap Control Panel. |
2. | Tap Printers and Other Hardware, and then tap Tablet and Pen Settings. |
3. | Tap the Display tab. |
4. | Under Screen brightness, in the Settings for list, tap the scenario that you want your settings to apply to. |
5. | To make the screen darker or brighter, move the slider to the left or to the right. |
6. | Tap OK. |
Turning Off Power-Consuming Peripherals
Peripheral devices on your computer use power. For instance, your Tablet PC may have a wireless network connection, a modem card, USB devices, FireWire devices, or an IR port. Because some of these peripherals can draw a significant amount of power, you should consider unplugging them or turning them off in situations where you want to conserve battery power. For information on turning off your wireless network connection or your IR port, please refer to the manufacturer's documentation.
Using Power Schemes
Power schemes are a collection of settings that manages the power usage of your computer. You can select from a number of power schemes that are available in Power Options in the Control Panel, you can adjust individual settings of any available power scheme, or you can create your own power schemes to suit your particular system and preferences.
For a more detailed description of selecting, adjusting, and creating power schemes, see How to Use Power Schemes.
Using Standby and Hibernation Features
Standby is a low-power state in which your monitor and CPU turn off. When you want to use the computer again, it comes out of standby quickly and your desktop is restored exactly as you left it. Use standby to save power when you will be away from the computer for a short time while working.
Hibernation is a state in which your computer shuts down to save power but first saves everything in memory on your hard disk. When you restart the computer, your desktop is restored exactly as you left it. Use hibernation to save power when you will be away from the computer for an extended time.
Standby and hibernation settings can be controlled in a number of ways. These are discussed in detail in How to Use Standby and Hibernate.
