WINDOWS 1002000 PROFESSIONAL RESOURCE KIT [Electronic resources] نسخه متنی

Configuring Power Management

Power management allows you to configure how a computer consumes energy. In Windows 2000, power management is based on the ACPI architecture implementation, which is based on the OnNow design initiative for power management. The OnNow design initiative is a comprehensive, system-wide approach to system and device power control based on a group of new specifications. The ACPI architecture gives the operating system complete control of power use on the computer. Windows 2000 also supports some implementations of the APM architecture. However, APM does not give Windows 2000 control of the power being used by devices (that is, power that is controlled by the BIOS), and your ability to manage power is more limited with APM-based computers than it is with ACPI-based computers.

Even if you do not have an APM-based or an ACPI-based computer, Windows 2000 allows you to manage some aspects of power consumption. For example, depending on the capabilities of your hardware, you can power down disks, turn off power to monitors, and put the computer into hibernate mode.

This section discusses power management in Windows 2000. It includes procedures for configuring and using power management as well as procedures for identifying whether your computer is ACPI-based, APM-based, or neither.

ACPI Power Management

Windows 2000 directs power management through the ACPI system. Unlike previous approaches to power management, ACPI manages power for the entire system, including all system devices and peripherals. To make this possible, the operating system must direct power to the computer. Older power management architectures, such as APM, do not do this. For these systems, the BIOS controls the power state of system devices. However, ACPI makes it possible for the operating system to coordinate power management activities at all levels and define the power-state transitions for the system.

With ACPI power management, the computer has the ability to function as follows:

The computer is be ready for immediate use when the user turns it on.

The computer appears to be off when not in use, but it can still respond to wakeup events. wakeup events can occur when a device receives input, such as a telephone ringing, or when software requests that the computer wake up at a predetermined time (for example, to download e-mail so it is ready in the morning).

The system can change how software responds when the power state of the computer changes. The operating system and applications work together intelligently to operate the computer and deliver effective power management according to the user's current actions. Applications do not keep the computer busy unnecessarily; instead, they proactively participate in shutting down the computer to conserve energy and reduce noise.

All devices can participate in the power management scheme, whether the device was originally installed when Windows 2000 was installed or it was added as a peripheral after Windows 2000 was installed.

Figure 10.1 shows the components of the ACPI system.

Figure 10.1 ACPI System Components

Applications that were developed before ACPI was available were designed with the assumption that the computer is always fully powered while the application is running. Such applications can inadvertently keep the system from entering a lower power state. In addition, these applications can fail if the computer enters standby mode or hibernate mode and then wakes up.

Managing Power with ACPI

In ACPI, power policy is based on the end user's preferences, the application requirements, and the system hardware capabilities. In other words, although Windows 2000 supports ACPI, applications need to be designed to work with ACPI power management and Plug and Play to make the entire process seamless.

The operating system controls energy use by putting the computer into a low-power state (for example, standby mode) when the computer is not in use. What determines how to save energy and when to go into a low-power state is referred to as the operating system's power policy. Power policy is distributed throughout the system, with system components acting as policy owners. For example, the operating system itself is the policy owner for determining when the computer should go into standby mode and hibernation mode and how to operate the processor to obtain energy conservation and meet thermal and audible noise goals.

There is also a policy owner for each device class on the computer. The policy owner for a particular device class is the component that is aware of how the device is used by the end user and the applications. This is generally a high-level component and in most cases a Win32 Driver Model (WDM) class driver. Each policy owner must manage power appropriately for its class and work consistently with the operating system's policy for putting the computer into a low-power state such as standby mode or hibernate mode.

How ACPI Works

For the ACPI system to be successful, Windows 2000 must be aware of how power management features integrate throughout the computer. This is done through the ACPI implementation, which is based on the OnNow design initiative. This feature is a system interface that provides a standard way of controlling the power management and Plug and Play functions of the computer hardware. ACPI allows the operating system to automatically turn on and turn off standard devices, such as CD-ROMs, network adapters, hard disk drives, and printers, as well as consumer devices that are connected to the computer, such as video recording and play-back devices, televisions, telephones, and stereo phonograph and CD players.

For a system to be completely OnNow capable, the system BIOS must support ACPI. The BIOS plays an important role in the ACPI by working with Windows 2000 to perform the necessary initialization processing and handoff during startup and when the working (full power) state is resumed from standby mode or hibernate mode. Figure 10.2 is an overview of the ACPI.

Figure 10.2 Overview of the ACPI

The ACPI specification has two parts: configuration (Plug and Play), and power management. ACPI gives Windows 2000 and the device drivers full control over power management. The BIOS provides Windows 2000 with access to the hardware controls for controlling power in the system. Windows 2000 and the device drivers, which are aware of the system's active state, determine when to turn off devices that are not in use and when to put the entire system into standby or hibernate mode.

Because power management is controlled by the operating system, there is a single user interface for managing power that works on all ACPI computers and simplifies the experience for the end user. ACPI also provides details to the operating system about system capability and sources of events. For example, an ACPI computer and operating system can do the following:

Be sure the screen does not turn off in the middle of a presentation.

Allow the machine to "wake" at a specified time to perform a task but not turn on the monitor and drives needlessly.

Allow the user to choose what the power and reset buttons on the computer do to the operating system. You can configure the power button so that it does not shut down the computer. Instead, it puts the computer into standby mode.

In contrast to ACPI, there is the APM BIOS version 1.2 specification. With APM, the BIOS controls system power management. The BIOS has timers that monitor most interrupts and the data that is being transmitted through the input/output (I/O) port. When the timer for a device exceeds a value set in the BIOS setup, the BIOS turns off the device. When the system-wide timer exceeds some value set in the BIOS, the BIOS sends a message to Windows 2000 to put the entire computer in a low-power state. Windows 2000 then verifies that the computer is ready to be placed into standby mode or hibernate mode, and it tells the BIOS to do so. The APM BIOS is also responsible for monitoring the battery status and requesting a low power state if the battery is getting low. In general, APM has the following limitations:

Inconsistent user interfaces. Each BIOS has its own user interface and its own power management behavior. This means every computer operates differently—users have to be retrained on each computer.

Reasons for suspend are not known. Because of the architecture of the APM BIOS interface, the APM BIOS cannot inform Windows 2000 that a request is a response to the user pushing a sleep button, to the BIOS sensing that the system is idle, or to the battery running out of power. As a result, Windows 2000 must always honor this suspend request and attempt to put the computer into low-power state—even if the computer is not idle. For this reason, it is recommended that you set the BIOS time-out settings to a very large value or turn them off.

Devices might be turned off at inappropriate times. By monitoring I/O ports and interrupts, the BIOS is essentially trying to determine what the user and the applications are doing. Although this often works, there are many scenarios in which the response of the BIOS is incorrect—for example, the BIOS turns off or slows down a computer when it is in use (such as a screen saver turning on in the middle of a presentation), or the BIOS does not turn off a truly idle computer.

BIOS detects activity only on devices that are residing on the motherboard. The BIOS cannot detect devices that are not on the motherboard, such as USB devices and IEEE 1394 devices. As a result, the system might appear to the BIOS as if it were not in use, even if one or more of these off-motherboard devices actually is in use.

In addition to these general limitations, there are several limitations specific to Windows 2000:

Windows 2000 only supports the following APM features: battery status, suspend, resume, and hibernate. it does not support other APM features such as timer wake up, wake-on-local area network (LAN), or wake-on-ring.

APM is supported only on portable computers.

APM is not supported in the Windows 2000 server family of products.

APM does not work with multiprocessor systems.

In the following section, APM and how you can configure APM so that it works with Windows 2000 Professional are discussed.

BIOS Compatibility and Configuration

To use ACPI-based or APM-based power management features with Windows 2000 Professional, the ACPI-based BIOS on your computer must be fully ACPI-compliant, or the APM-based BIOS on your computer must be compatible with Windows 2000. In addition, you must configure an APM-based BIOS in order for power management to work properly with Windows 2000.

Checking ACPI Compliance

During setup, Windows 2000 determines which hardware abstraction layer (HAL) to install on a computer. This determination is based on whether a computer has a compliant ACPI BIOS or not. If it does, the ACPI HAL is installed and you are able to use the ACPI power management features; if it doesn't, an older HAL is installed and the ACPI power management features are not available.

NOTE

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In general, the HAL directs information from the operating system and device drivers to specific devices. ACPI-based computers require an ACPI HAL. Non-ACPI-based computers require an older HAL.

To determine which HAL to install, Windows 2000 performs the following procedures during setup:

Windows 2000 checks the ACPI BIOS tables that are generated during startup. These tables list the devices that are installed on the computer and their power management capabilities.

If this information is missing or if the information is in the wrong form, an older HAL is installed.

If the tables are correct, Setup checks whether the BIOS is known to be incompatible or non-compliant with the ACPI standard.

If the BIOS is incompatible, an older HAL is installed.

If the BIOS is not on the incompatible BIOS list, Setup looks at the BIOS date.

If the BIOS is not on the incompatible BIOS list and the BIOS date is later than 1/1/99, Windows 2000 accepts it, and the ACPI HAL is installed.

If the BIOS is not on the incompatible BIOS list and the BIOS date is earlier than 1/1/99, Setup looks for a compatible BIOS.

If the BIOS is on the compatible BIOS list, an ACPI HAL is installed.

If the BIOS is not on the list, an older HAL is installed.

You can check a computer's BIOS compatibility on the Microsoft Windows Hardware Compatibility List (HCL) Web site. For more information about the HCL, see the Hardware Compatibility List link on the Web Resources page at http://windows.microsoft.com/windows2000/reskit/webresources. If you have already installed Windows 2000, you can check to see whether the computer is operating in ACPI mode by following this procedure.

To determine whether Windows 2000 is running in ACPI mode

From the Start menu, point to Settings, and then click Control Panel.

Double-click Administrative Tools, and then double-click Computer Management.

In the view pane, click Device Manager.

In the details pane, click System devices.

If Microsoft ACPI-Compliant System is listed under System devices, the computer is operating in ACPI mode.

If you have an ACPI BIOS but Windows 2000 didn't install in ACPI mode, you might have a non-compliant ACPI BIOS. Check your computer manufacturer's Web site to see whether a more recent ACPI BIOS version is available. If one is available, you have an older HAL installed on your computer, and you flash a new BIOS version on to your computer, you must reinstall Windows 2000. Reinstalling Windows 2000 is the only way to replace an older HAL with an ACPI HAL. For more information about upgrading the BIOS in a portable computer, see the Hardware Update link on the Web Resources page at http://windows.microsoft.com/windows2000/reskit/webresources.

To determine which hardware abstraction layer is installed

Find Hal.dll (which located in %SystemRoot%system32).

Click the file, and on the File menu, click Properties.

In the hal.dll Properties dialog box, click the Version tab.

On the Version tab, in the Other version information box, in the Item name pane, click Original Filename.

Look under Value.

If halacpi.dll is listed, an ACPI HAL is installed on the computer. If hal.dll is listed, a previous HAL is installed.

NOTE

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ACPI functionality is new, and features are being added by BIOS manufacturers and system manufacturers. If functionality is missing that you believe should exist, if you are experiencing unusual behavior with a BIOS that is dated later than 1/1/99 or a BIOS that is listed on the compatible BIOS list, verify with the computer manufacturer that you have the most current BIOS revision installed on the computer.

Checking APM BIOS Compatibility

Windows 2000 supports APM version 1.2 on portable computers, but the computer must have a compatible APM BIOS for APM features to work properly. Windows 2000 determines whether a BIOS is APM-compatible during setup. On the basis of this determination, Windows 2000 does one of the following:

Installs APM support (Ntapm.sys and Apmbatt.sys) and enables APM if the computer's BIOS is found on the auto-enable APM list. APM is fully functional after setup completes.

Does not install or enable APM support if the computer's BIOS is found on the disable APM list. APM does not work reliably, and it should not be used on the computer, or data loss might occur.

Installs APM support but does not enable APM support if the computer's bios is not on the auto-enable APM list or the disable APM list. APM might work properly, but you have to enable APM in the Windows 2000 graphical user interface (gui) for APM to be enabled. (see "Enabling and Configuring APM" in later this chapter.)

IMPORTANT

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APM must be enabled in the BIOS before Windows 2000 is installed. If APM is disabled in the BIOS before installation, Windows 2000 does not install power management support even if the APM BIOS is on the auto-enable APM list.

If APM is not enabled after you install Windows 2000, either the computer's BIOS is on the disable APM list, or it is not on either the disable APM list or the auto-enable APM list. You can determine this by running the Apmstat.exe tool, which is part of the Windows 2000 Support Tools. The Windows 2000 Support Tools are included on the Windows 2000 Professional operating system CD.

To install the Windows 2000 support tools

Run Setup.exe, which is located in the SupportTools folder on the Windows 2000 Professional operating system CD.

The Apmstat.exe tool must be run from the command line. It has one command line switch (-v), which indicates that you want the tool to run in verbose mode. You do not need to run the tool with the -v switch in order to determine APM BIOS compatibility.

To check APM BIOS compatibility by using Apmstat.exe

From the Start menu, point to Programs and then Accessories, and then click Command Prompt.

Type:

apmstat

Press ENTER.

If Apmstat.exe reports that an APM BIOS is known to be incompatible or that an APM BIOS is known to have problems, you must not attempt to circumvent Windows 2000 Setup by forcing it to install APM support. This might cause a computer behave erratically, and it might result in the loss of data. In addition, if an APM BIOS is known to be incompatible, make sure that APM is disabled in the BIOS.

If Apmstat.exe reports that an APM BIOS is not known to be compatible and it is not known to be incompatible, you might still be able to use APM, but you need to enable and configure APM in order for it to work effectively on your computer.

Enabling and Configuring APM

APM must be enabled before you can use it. However, you can only enable APM if Windows 2000 installed APM support during setup. You can verify whether APM support is installed by using Device Manager. Enabling APM does not require that you restart the computer; however, disabling APM does require it.

To verify that APM support is installed on a computer

From the Start menu, point to Settings, and then click Control Panel.

Double-click Administrative Tools, and then double-click Computer Management.

In the view pane of Computer Management, click Device Manager.

On the View menu, click Show hidden devices.

If NT Apm/Legacy Support is present in the details pane, APM support is installed.

To enable APM

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the APM tab.

On the APM tab, in the Advanced Power Management check box, click Enable Advanced Power Management support?

NOTE

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The APM tab is present only if an APM BIOS is detected that is either APM 1.2 compliant or might not be APM 1.2 compliant but might work. It is not reccomended that you enable APM support on a computer that has a BIOS that is not APM compliant. If you experience problems after enabling APM support, disable APM and contact the computer manufacturer for an updated BIOS. In addition, the APM tab is not present if a computer has multiple processors because Windows 2000 does not install APM support on multiprocessor computers.

You can verify that APM is enabled and running by looking at the Shut Down Windows dialog box. This procedure only works on computers that have a non-ACPI BIOS

To verify that APM is running on a computer

Click Start, and then click Shutdown.

In the Shut Down Windows dialog box, under What do you want the computer to do?, look for Stand by. If it is present, APM is running.

Although Windows 2000 supports APM, you might have to configure two settings in the APM BIOS before APM works properly. First, configure BIOS time-outs to the longest possible time or disable them. This allows the operating system rather than the BIOS to control time-outs. Be aware that some APM BIOSs turn off or refuse to function if all time-outs are disabled, so it might be better to set time-outs to the maximum allowed time rather than disabling them. Second, make sure that screen blanking is turned off in the BIOS. Screen blanking reduces power to the display, which causes the display to appear as though the computer is shut down. Normally, activating a pointing device wakes the system and restores power to the display. However, USB and other external pointing devices do not wake the system, and power is not restored to the display. You can usually turn off screen blanking in the BIOS by disabling the time-out for the display or by setting the time-out to the maximum value.

Finally, do not use a supplemental video card with a portable computer if you are using APM. Only use the video card that is included with the portable computer. The APM BIOS might not detect a video card that is added to the system or a video card that is in a docking station. If the adapter is not discovered by the APM BIOS, suspend does not work.

Power Management Options

Whether you have an ACPI-based or an APM-based computer, you must enable or configure the power management options; otherwise, they do not function properly. This includes choosing and configuring a power scheme, enabling hibernate mode and the battery status indicator, and configuring the power button and the battery alarms.

Configuring Power Schemes

Power schemes allow you to configure how and when a computer turns off devices or enters a suspend state. For example, you can set individual power-down settings for the monitor and the hard disk. (Depending on the computer's hardware capability, you might be able to configure these settings even if the computer is not ACPI-enabled or APM-enabled.) If the computer is ACPI-enabled or APM-enabled, you are also able to configure power-down settings for standby mode and hibernate mode, although you must first enable hibernate mode or it is not available. (For information about how to do this, see "Hibernate Mode and Standby Mode" later in this chapter.) ACPI and APM also allow you to configure these settings separately depending on whether the computer is powered by alternating current or a battery. There are six default power schemes: Home/Office Desk, Portable/Laptop, Presentation, Always On, Minimal Power Management, and Max Battery. You can customize any scheme or add new schemes to fit a specific situation.

You need to configure the power scheme for a portable computer because the default power scheme is Home/Office Desk, which does not optimize battery power. The power scheme might also need to be changed according to how the computer is used. The Presentation scheme is useful because it prevents the computer from entering standby mode or hibernate mode.

To configure power schemes

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Power Schemes tab.

Select a power scheme, and then change any of the settings you want.

When a computer enters hibernate mode, the current state of the computer is saved to disk and the power to the computer is turned off. When a computer resumes from hibernation, it reads the state data from the disk and restores the system as it was before it entered hibernate mode. Software programs are restarted, and network connections are restored.

Hibernate mode must be enabled; by default, it is disabled. If a computer is not ACPI-enabled or APM-enabled, you are able only to enter hibernate mode manually. You are not able to set the computer to autohibernate after a certain time. ACPI-enabled and APM-enabled computers are able to enter hibernate mode automatically. Resuming from hibernate mode requires users to enter a user name and a password. This setting cannot be changed.

Because the contents of the computer's memory are written to disk when it enters hibernate mode, you must have at least as much available disk space as you have random access memory (RAM) installed on your computer.

To enable hibernate mode

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Hibernate tab.

Click Enable hibernate support.

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You must have the proper hardware to use hibernate mode. If the Hibernate tab is not available, the computer does not support hibernation.

When a computer enters standby mode, the computer's state is not saved to a disk; rather, it puts the computer in a low-power state. When a computer resumes from standby mode, full power is restored to devices. If the power is interrupted when the computer is in standby mode, data might be lost. You do not have to enable standby mode in order for it to be available. It is available automatically on ACPI-enabled and APM-enabled computers. It is not available on non-ACPI-based or non-APM-based computers.

You can have the computer prompt the user for a user name and password after it resumes from standby. This is enabled by default.

To disable password protection when resuming from standby mode

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Advanced tab.

Click the Prompt for password when computer goes off standby check box to clear it.

Group Policy allows you to configure the policy refresh interval, which controls how often policies are applied on the computer. By default, the refresh interval is 90 minutes, although it can be set to any value between 0 minutes and 64,800 minutes. In addition to the refresh interval, you can set an interval offset, which is a random period of time that is applied to the refresh interval. The interval offset randomizes the refresh interval and prevents clients with the same refresh interval from simultaneously requesting policy updates, which can overload the server. By default, the interval offset is 30 minutes, which means a random time between 0 minutes and 30 minutes is applied to the refresh interval.

In some cases, Group Policy refresh settings can prevent a computer from entering hibernate mode or standby mode. This is because a policy update resets the hibernation or standby timer (just like moving the mouse or pressing a key on the keyboard). For example, if a computer is configured so that it enters hibernate mode or standby mode after being idle for 45 minutes but the Group Policy refresh interval is set at 30 minutes, the hibernation or standby timer never reaches 45 minutes. To ensure that the standby timer does not reach 45 minutes, set the Group Policy refresh interval so that it is greater than the hibernation setting or standby setting in Power Options. You can also configure Group Policy so that it does not apply settings while the computer is running. The descriptions of the procedures follow.

To change group policy refresh interval and interval offset for user configuration settings

From the Start menu, click Run, and then type:

gpedit.msc

Press ENTER.

In the view pane of Group Policy, under User Configuration, open the Administrative Templates folder, and then open the System folder.

Click Group Policy.

In the details pane, double-click Group Policy refresh interval for users.

In the Group Policy refresh interval for users Properties dialog box, click Enabled.

Change the settings for the refresh interval and the interval offset.

To change group policy refresh interval and interval offset for computer configuration settings

From the Start menu, click Run, and then type:

gpedit.msc

Press ENTER.

In the view pane of Group Policy, under Computer Configuration, open the Administrative Templates folder, and then open the System folder.

Click Group Policy.

In the details pane, double-click Group Policy refresh interval for computers.

In the Group Policy refresh interval for users Properties dialog box, click Enabled.

Change the settings for the refresh interval and the interval offset.

To disable policy updates while a computer is running

From the Start menu, click Run, and then type:

gpedit.msc

Press ENTER.

In the view pane of Group Policy, under Computer Configuration, open the Administrative Templates folder, and then open the System folder.

Click Group Policy.

In the details pane, double-click Disable background refresh of Group Policy.

In the Disable background refresh of Group Policy Properties dialog box, click Enabled.

Some commercial airlines might request that you turn off portable computers during portions of a flight, such as takeoff and landing. To comply with this request, users must turn off their computer completely.

A computer might appear to be turned off while it is in either standby or hibernate mode. However, the operating system might automatically reactivate itself to run certain preprogrammed tasks or to conserve battery power. To prevent this from occurring during air travel, be certain that users shut down their computer completely when it is not in use. For more information about shutting down a computer, see Windows 2000 Professional Help.

In addition, if a computer is equipped with a cellular modem, users must ensure that this modem is completely turned off during air travel as required by Federal Communication Commission regulations.

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Failure to comply with these requirements could lead to civil or criminal penalties.

Battery Monitoring and Management

Battery monitoring and management is only available on ACPI-enabled and APM-enabled computers. Windows 2000 can manage batteries that have a Smart Battery subsystem interface or a Control Method Battery (CMBatt) interface. Windows 2000 can also monitor multiple batteries.

You must enable the battery status icon in order for it to appear on the taskbar. This icon gives users direct access to the power meter so that they can monitor the battery level.

To add the battery status icon to the taskbar

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Advanced tab.

Click the Always show icon on the taskbar check box.

You can also configure the battery meter so that it displays the status of multiple batteries if your portable computer uses multiple batteries.

To configure the battery meter for multiple battery computers

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Power Meter tab.

Click Show details for each battery.

You can also set alarms to indicate low battery and critical battery levels. You can set the alarm to be a notification (visual or audible), a change in power state (standby, hibernate, shutdown), or the execution of a program.

To configure alarms

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Alarms tab.

Drag the sliders to change the battery level at which a low-battery alarm and a critical-battery alarm are activated.

Click Alarm Action to configure the actions you want taken when an alarm is activated. You must configure alarm actions separately for low-battery and critical-battery actions.

ACPI-enabled computers allow you to change how the power button behaves when you press it. There are three options: Power Off, Standby, and Hibernate. By default, none of these options are assigned to the power button. If you change the power button functionality to Standby or to Hibernate, the computer enters the specified modes when the user presses the power button. To resume from these modes, the user also presses the power button. If you change the power button functionality to Power Off, the computer immediately powers down when the user presses the power button. This type of power down is not the same as shutting down the computer by clicking Shut down from the Start menu. Using the Shut down command prompts users to save data (if necessary) and then flushes the hard drive cache. When the Power Down option is set, and the user presses the power button, the hard drive cache is not flushed and the user is not prompted to save data (even if there are open documents or files).

To change power button functionality

From the Start menu, point to Settings, and then click Control Panel.

Double-click Power Options.

In the Power Options Properties dialog box, click the Advanced tab.

Under When I press the power button on my computer, select the power button functionality you want.

CAUTION

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Setting power button functionality to Power Off could result in the loss of data if files or documents are open when a user presses the power off button. The Power Off option is a quick and fast method of turning off power to the computer. It is not the recommended method for powering down a portable computer. The recommended method is to use the Shut down command on the Start button.

Wake-On Technology

"Wake-On" technology allows individual devices to resume for certain actions without requiring the rest of the system to start up. Windows 2000 supports Wake-On features such as wake-on-ring and wake-on-LAN, but only on ACPI-based computers. Windows 2000 does not support wake-on-LAN or wake-on-ring if the PC Cards you are trying to wake require CardBus technology.

Hiding Power Options

You can prevent users from configuring power options by specifying Control Panel settings in Group Policy. You can disable Control Panel entirely, hide specific Control Panel tools, and show specific Control Panel applets. Hiding the Power Options tool can be beneficial if you have configured power options and it is imperative that users not change those options. However, if you hide Power Options, users have no method for reconfiguring power management settings if something needs to be changed while they are away from the office. For example, portable computer users frequently use the Portable/Laptop scheme, but when they use the portable computer for a presentation, they should switch to the Presentation scheme to prevent the portable computer from turning off the display or entering standby mode or hibernate mode. Users are not able to change power schemes, or any other power option, if Power Options is not available.

To hide power options by using group policy settings

From the Start menu, click Run, and then type:

gpedit.msc

Press ENTER.

In the view pane of Group Policy, under User Configuration, open the Administrative Templates folder.

Click the Control Panel folder.

In the details pane, double-click Hide specified control panel applets.

In the Hide specified control panel applets Properties dialog box, click Enabled, and then click Show.

In the Show Contents dialog box, click Add.

In the Add Item dialog box, type:

power options

Click OK.

Power Options should show up under List of disallowed Control Panel applets in the Show Contents dialog box.

To disable the control panel by using group policy settings

From the Start menu, click Run, and then type:

gpedit.msc

Press ENTER.

In the view pane of Group Policy, under User Configuration, open the Administrative Templates folder.

Click the Control Panel folder.

In the details pane, double-click Disable Control Panel.

In the Disable Control Panel Properties dialog box, click Enabled.

IMPORTANT

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Disabling Control Panel in Group Policy prevents Control.exe from starting. This removes Control Panel from the Start menu and removes the Control Panel folder from Windows Explorer.