Power Management and UPS

A computer’s Basic Input/Output System (BIOS) is software through which the operating system communicates with hardware devices. Advanced Configuration and Power Interface (ACPI) is the current standard for the way the BIOS works. Windows supports not only ACPI but also some BIOS versions based on older Advanced Power Management (APM) designs. Some machines aren’t capable of supporting the ACPI standard, and in some the APM feature actually conflicts. Consult the HCL and be prepared to disable APM in the BIOS.

Use the buttons below to navigate through the lesson



Power consumption of a computer’s  devices or an entire system can be reduced using Power Options. This is done by choosing a power scheme, a collection of settings that manages the computer’s power usage. A user can create his or her own power schemes ,or use the schemes provided with Windows. Power consumption of a computer’s  devices or an entire system can be reduced using Power Options. This is done by choosing a power scheme, a collection of settings that manages the computer’s power usage. A user can create his or her own power schemes ,or use the schemes provided with Windows. Power Options are available to any Windows XP machine, but they are especially important  to preserve battery life for laptop users.

Start > Control Panel > reveals this window.

If Power Options are available on the machine, this icon will be seen. Click on it……and the Power Options applet is revealed.  The tabs available may vary from machine to machine, but these are typically seen on a desktop machine.

This is the more complex display typically seen on a laptop computer.

The current settings are for a light use desktop computer. Note the power-hungry monitor will shut down if it’s idle for 20 minutes, but the hard drives remain live for a quick resumption of working.  In this configuration the monitor and the hard drive shut down to preserve battery power.  These settings can be altered to give a more ruthless power saving.  Save these changes to make a  new Power Option.

Once given a distinctive name, the option becomes available for future use.  The drop down window reveals the list of ready-made power options.

A basic ready-made option can be selected and used as it is, or settings for the monitor and hard drive can be modified for each option.

This tab presents an unimpressive set of choices. The option to have the indicator on the taskbar is a useful one, however.

Hibernation will allow you to save your computer’s current state before powering down. This will allow you to reboot the computer quickly, returning you to your previous session.

UPS Devices

These come in all shapes and sizes but essentially do the same job. In the event of a mains failure they provide emergency battery power to keep a system alive until it can be safely shut down, or until the power is restored.

A UPS device should do its basic job merely by being plugged in. However, it can only be configured by starting the UPS service.

First, the device has to be identified to the system.

Once a device has been selected options for configuration become available…Choose one, and click finish.

While the basic UPS function works as soon as the unit is plugged in, the configurable settings only work when the UPS Service is started. Unfortunately, no clue appears on screen as to whether the service is running or not. Delve into Administrative tools for this…

This list of services is accessed through Computer Management > Services.  The service needs to be started manually. (Right-clicking brings up the required menu.)