Replacing the battery

The battery (3.3V) provides power for the system real-time clock and CMOS RAM, which holds the system configuration information.

If your battery is failing you may notice your system clock slowing down and giving you the incorrect time. If so, open the BIOS Setup utility and write down all the values in the BIOS Setup utility screens before replacing the battery. Replacing the battery resets the BIOS Setup utility to its default values.

Caution There is a danger of explosion if the battery is incorrectly replaced. Replace the battery only with the same or equivalent type recommended by the manufacturer. Dispose of used batteries according to the manufacturer’s instructions.

To replace the battery:

1Restart the computer and start the BIOS Setup utility by pressing F1 when you are prompted to do so.

2Write down the CMOS values from the Main Setup utility screens so you can reenter them after you replace the battery. (For more information, see “About the BIOS Setup utility” on page 63.)

3Turn off the computer, disconnect the power cord, modem cord (if installed), and all external peripheral devices.

4Remove the right panel. (See “Removing the side panels” on page 19 and observe the “Static electricity precautions” on page 17.)

5Locate the battery on the system board (see “System board” on page 8). The battery is circular and has the positive pole mark (+) on the top.

Positive pole symbol

6Using your fingers to grasp the sides of the battery, carefully remove the battery from its socket.

50Replacing and Adding System Components