Hardware Reference
In-Depth Information
password) at the prompts.
Table 5.20
shows the security functions in a typical BIOS Setup.
Table 5.20. Security Settings Menu
To clear passwords if the password is forgotten, most motherboards have a password-clear jumper
or switch. Intel motherboards require that you set the configuration jumper, enter the Maintenance
menu in BIOS Setup, and select the Clear Password feature. If you can't find the documentation for
your board and aren't sure how to clear the passwords, you can try removing the battery for 15
minutes or so—it clears the CMOS RAM. It can take that long for the CMOS RAM to clear on some
systems because they have capacitors in the circuit that retain a charge. Note that this also erases
other BIOS settings, including the hard disk settings, so you should record them beforehand.
Power Menu
Power management
is defined as the capability of the system to automatically enter power-
conserving modes during periods of inactivity. Two main classes of power management exist; the
original standard was called Advanced Power Management (APM) and was supported by most
systems since the 386 and 486 processors. More recently, a new type of power management called
Advanced Configuration and Power Interface (ACPI) has been developed and began appearing in
systems during 1998. Most systems sold in 1998 or later support the more advanced ACPI type of
power management. In APM, the BIOS does the actual power management, and the OS or other
software has little control. With ACPI, the power management is done by the OS and BIOS together.
This makes the control more centralized and easier to access, and it enables applications to work
with the power management. Instead of using the BIOS Setup options, you merely ensure that ACPI is
enabled in the BIOS Setup and then manage all the power settings through the Power configuration
settings in Windows 98 and later.
Table 5.21
shows the typical power settings found in a managed system.
Table 5.21. Power Settings Menu
