- 1). Unplug the computer and move it to your work area, making sure to ground yourself to the computer using an anti-static wristband before opening the computer case, in order to remove any risk that static discharge may damage one of your computer's internal components.
- 2). Use the screwdriver to remove the screws that attach the cover to the case. Do not touch anything else inside the computer, and do not drop anything inside the computer.
- 3). Locate the CMOS battery on the motherboard: it is circular and metallic, and about the size of a quarter. Observe how it is held in place; then use your fingers to gently push apart the latches holding it in place, and remove it.
- 4). After removing the CMOS battery, leave it out of the computer, resting on a non-conductive surface, such as a wooden table, for 15 to 20 minutes, allowing the power in the capacitors and transformers time enough to discharge, rendering the computer powerless. This will revert the BIOS to its factory settings.
- 5). Reinstall the battery in its place on the motherboard, and reattach the cover to the case. Plug all computer cords back in.
- 6). Turn on the computer and enter the BIOS; no password should prevent you from entering the BIOS. (You may have to adjust your computer's date and time once you have logged back in.)
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