How to Reset BIOS

By Techwalla Computers Editor

All of a computer system's start-up processes are located in an area on the motherboard known as the BIOS, or Basic Input Output System. This area of instructions resides on a memory chip known as the CMOS. The independently powered CMOS and BIOS get their power from a small button cell battery. There are a few steps involved in order to clear and reset the BIOS.

Step 1

Power the computer system all the way down. Remove the power cord and hold the power button in for a few seconds to clear any remaining charges.

Step 2

Open the computer case by removing any thumbscrews or screws from the rear or side of the computer case. A panel will slide away revealing the inside of the case and the computer's motherboard.

Step 3

Locate the small button cell battery held in place by a small arm on the motherboard. Gently remove the button cell battery from its location.

Step 4

Look for a set of jumper pins near the button cell battery with a marking of "PASS" or "BIOS" stamped on the motherboard. There are three pins in a row connected together with a small black jumper. Typically the 1 and 2 pins are connected. Remove this jumper pin and connect to the other 2 pins. Wait for a few seconds and replace the jumper in its original location.

Step 5

Place the button cell battery back into its original position and listen for it to snap back into place. Return the case panel into position and re-tighten the thumbscrews holding it in place.

Step 6

Return power to the computer and reboot. The system may now ask for a password or to reset the password.

Tips & Warnings

  • Replace the small button cell battery while the case is open. These are available at any retailer, such as Wal-Mart or Target.
  • Clean the case while it is open. Blow compressed air into the computer case to dislodge any dust or debris.
  • Never work on a computer case before discharging any static charges from the body. Touch the inside of the case to dissipate any charge.