How to Replace the BIOS Battery on a Compaq Presario 1200
- 1). Turn off your Compaq Presario and unplug it from AC power. Close the laptop, turning it over so that the base of the unit is facing up, and remove the battery.
- 2). Remove the five screws on the bottom of the Presario 1200's case and set them aside. Set the laptop upright and open it.
- 3). Remove the palm rest, being careful not to unplug the touch pad. Lift the edge of the keyboard and pull it toward you to remove it, setting it aside (again being careful not to unplug it).
- 4). Unscrew the four screws holding the heat sink plate in place. Remove the heat sink, granting you access to the motherboard.
- 5). Locate a small, square chip on the motherboard with a round battery located next to it. The chip is the CMOS chip which stores the BIOS information, and the battery is the BIOS battery.
- 6). Use your craft stick or bamboo skewer to carefully push the battery out of the plastic clip that holds it in place. Insert your new battery, making sure that the top and bottom of the battery are oriented in the same direction as the previous one.
- 7). Replace the heat sink, keyboard and palm rest. Turn the Presario 1200 over and replace the screws that you previously removed from the bottom of the case.
- 8). Insert the laptop battery and plug the laptop back in if you wish to use AC power. Turn the Presario upright and boot the computer.
- 9). Wait for an error to appear concerning incorrect BIOS settings. Press the indicated key to enter BIOS setup.
- 10
Set the date and time on your Presario 1200 manually, then save your settings and exit BIOS setup. Hardware settings will be set automatically, and upon exiting BIOS setup, the laptop will reboot and load your operating system as normal.
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