- 1). Turn the Dimension 8400 off. After removing all of the cords and peripherals, test your desk to make sure that it can hold the computer's weight. If you aren't sure, relocate the computer tower to the kitchen table instead. When placing the tower on the table or desk, make sure that the padlock hoop on the back of the tower faces up. You can also find an indicator arrow on the bottom of the tower to confirm that you have oriented the tower correctly.
- 2). Press and hold the buttons at the back corners of the Dimension 8400 tower, then swing the side of the computer up and away from you to access the inside of the computer. Locate the old coin-cell battery on the computer motherboard.
- 3). Push the release button next to the Dimension 8400 battery to make it come out of the compartment. Lift the battery out of the computer and set it aside.
- 4). Install the new CR2032 battery in the empty compartment, making sure that the positive side, marked by a "+" icon, is on top.
- 5). Push the computer cover down to close the Dimension 8400 tower.
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