5-10 Solving System Problems
How to Replace the CMOS Battery
The system board uses a CMOS battery to maintain system configuration
information. The battery is a coin-cell battery mounted on the system
board (see the following figure). If it fails to maintain system
configuration information, replace it with an identically rated battery from
the same manufacturer.
The battery can explode if it is incorrectly
replaced or improperly discarded. Use only the same type battery or an
equivalent type recommended by the manufacturer when replacing the
battery.
Lithium acts as a catalyst when exposed to water and causes
spontaneous combustion on contact. Discard used batteries according to
the manufacturer’s instructions.
Removing the battery from the system board
causes the system to lose system configuration information. If possible,
prior to removing the battery, run the BIOS Setup Utility (see Chapter 3)
and print out or write down your system configuration settings. Then you
can restore the system to its previous settings.
If you need to replace the battery, follow these steps.
1.
Turn off and unplug the system and any external components
connected to it.
2.
Remove the system cover (see “Removing the Cover” in Chapter 4).
3.
Locate the battery on the system board (see the following figure).
4.
Remove any installed expansion boards that might be blocking access
to the battery (see “Removing an Expansion Board” in Chapter 4).
