How to clear an unknown BIOS or CMOS password

Updated: 08/02/2020 by Computer Hope

Sometimes, users encounter a password prompt at boot or the BIOS or CMOS setup is locked, as shown in the image below. If you do not know the BIOS password, you need to clear it. The following sections contain instructions on how to do so using multiple methods.

CMOS setup locked password screen

Note

The steps on this page are for a desktop computer. For a laptop computer, see: How do I clear a laptop BIOS or CMOS password?

Note

The steps on this page will not help to clear or reset a Windows password. To reset a password in Windows, see: How to reset a lost or forgotten Windows password.

Clear using jumper (recommended)

Follow these steps to clear the BIOS or CMOS password using a hardware jumper.

Caution

When working inside a computer, be sure you're aware of the potential damage that can be caused by ESD.

Computer jumper

On the computer motherboard, locate the BIOS clear or password jumper or DIP switch and change its position. This jumper is often labeled CLEAR, CLEAR CMOS, JCMOS1, CLR, CLRPWD, PASSWD, PASSWORD, PSWD or PWD. To clear, remove the jumper from the two pins currently covered, and place it over the two remaining jumpers. An example of the various jumper positions is shown in the image. Some computers may also clear the password by keeping the jumper open (one or no pins covered).

What if I can't locate the CMOS password jumper?

The following list details the general locations for the CMOS jumper. It's important to realize that most motherboards have multiple different jumpers, so you need to make sure you're changing the correct jumper. If you cannot find the password jumper, consult your motherboard's documentation by looking in the manual or downloading it from the manufacturer's website.

  1. On the edge of the motherboard - Most jumpers are on the side of the motherboard for easy accessibility. Verify by looking at all visible edges of the motherboard.
  2. By the CMOS battery - Some manufactures place the jumper to clear the CMOS or BIOS password by the CMOS battery itself.
  3. By the processor - Some manufactures place the jumpers by the CPU of the computer.
  4. Under the keyboard or bottom of laptop - On a laptop, the DIP switch are under the keyboard or on the bottom of the laptop. It is usually located in a compartment such as the one containing memory. (Laptops usually use DIP switches, not jumpers.)

Once the appropriate jumper or DIP switch is located and toggled, the password should be cleared. Turn your machine on to verify that the password has bee reset. Once cleared, turn the computer off and return the jumper or DIP switch to its original position.

Remove CMOS battery

CMOS battery

Removing the CMOS battery, like the one shown in the picture, causes the system to lose all CMOS settings, including the BIOS password. Locate and remove the CMOS battery from the motherboard for at least five minutes, then replace the battery and turn the computer back on.

Generic passwords

Try using generic CMOS passwords. It should be noted that many of these default passwords are for older motherboards and no longer work with newer machines.

Jump the CMOS solder beads

Older computers, especially older laptops, don't have jumpers or DIP switches. They require the user to jump a pair of solder beads on a circuit board. The identification and location of these solder beads can vary and if not available in the computer documentation, is only obtainable through the computer manufacturer.

If you've identified the solder beads, they can be jumped by placing a flat-head screwdriver over the two beads and leaving it on those beads while turning on the computer. Once the computer has booted, turn it off and then remove the screwdriver.

Contact manufacturer

If none of the previous sections resolved your issue, we recommend you contact the computer manufacturer or motherboard manufacturer for the steps on clearing the computer password.