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Setting Up and Troubleshooting Hardware Components and Device Drivers
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When Windows XP goes into standby, it turns off the monitor and hard
disks while maintaining power to memory. When you bring the computer
out of standby, your desktop appears exactly as you left it. You might want to
save your work before putting your computer on standby because, while your
computer is on standby, information maintained in memory is not saved to
your hard disk. If there is an interruption in power, information in memory
is lost.
To save even more power, Windows uses hibernation mode. The hibernate
feature turns off your monitor, saves everything in memory on disk, and
turns off the computer completely. When you restart the computer, your
desktop is restored exactly as you left it.
Hibernation takes longer, of course, due to the transfer of all memory-stored
data to the hard drive. Standby, however, is faster because it does not trans-
fer the current data stored in memory to the hard drive.
You can be sure to expect a number of questions on the exam to come out of hiber-
nation and standby. Your understanding of these options is likely to be tested.
Configuring and Troubleshooting ACPI Issues
The power options, like standby and hibernate, vary depending on the com-
puter’s hardware configuration. To use power options, the computer must be
ACPI-compliant, meaning that all components are capable of power man-
agement. If one or more components are not capable of power management,
you might either not have ACPI functionality or you might experience errat-
ic behavior.
To take full advantage of PnP, you must use an ACPI computer, running in
ACPI mode, and the hardware devices must be PnP. In an ACPI computer,
the operating system, not the hardware, configures and monitors the com-
puter.
ACPI lets the operating system direct power to devices as they need it, pre-
venting unnecessary power demands on your system.
Configuring and Troubleshooting System Power Options
A number of concepts and considerations are crucial to supporting power
management in Windows XP machines.
Users should put their computers in hibernation when away from the com-
puter for an extended time or overnight. When they restart the computers,
their desktops are restored exactly as they left them.