Clearing the BIOS/CMOS
5 mins
Easy
Tools Needed
CMOS is a small amount of memory on your computer's motherboard that stores BIOS settings. Clearing the CMOS resets these settings to their default values.
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When to Clear CMOS?
Clearing the CMOS is a straightforward process that can help resolve various issues with your computer. Always refer to your motherboard’s manual for specific instructions and precautions.
Reasons to clear the CMOS:
● Troubleshooting hardware issues
● Resetting BIOS/UEFI settings to default
● Resolving boot problems
● Overclocking failures
Steps to Clear the CMOS
Using the CMOS Jumper
Most motherboards have a CMOS jumper, typically labelled as "CLR_CMOS," "CLEAR," or "RTC."
• Turn Off Your Computer: Shut down your PC and unplug it from the power source.
• Locate the pins: Refer to your motherboard manual to find the exact location of the CMOS jumper.
• Short the pins: Some motherboards might just require you to short two pins with a metal object such as a screwdriver.
• Wait for 5-10 Seconds: Allow the metal object like a screwdriver to make contact with the pins for a few seconds.
• Power On the Computer: Once shorted, plug your PC back in and power it on to see if that assisted/did the trick.
Removing the CMOS Battery
The CMOS battery provides power to the CMOS chip to retain BIOS settings.
• Turn Off Your Computer: Shut down your PC and unplug it from the power source.
• Open the Case: Open your computer case to access the motherboard.
• Locate the CMOS Battery: Find the small, round battery on the motherboard. It looks like a coin.
• Remove the Battery: Carefully remove the battery by gently prying it out with a non-conductive tool.
• Wait for 5-10 Minutes: Leave the battery out for a few minutes to ensure the CMOS memory is cleared.
• Reinsert the Battery: Place the battery back into its holder.
• Power On the Computer: Plug your PC back in and power it on to see if that assisted/did the trick.
Using the BIOS/UEFI Menu
Some modern motherboards allow you to clear CMOS settings directly from the BIOS/UEFI interface.
• Enter BIOS/UEFI: Restart your computer and press the designated key (usually Del, F2, or Esc) to enter the BIOS/UEFI setup.
• Find the Reset Option: Navigate through the BIOS/UEFI menu to find an option like "Load Default Settings," "Reset to Default," or "Clear CMOS."
• Select the Option: Select the option and confirm any prompts.
• Save and Exit: Save the changes and exit the BIOS/UEFI.
Using a Reset Button (if available)
Some motherboards come with a dedicated CMOS reset button.
• Turn Off Your Computer: Shut down your PC and unplug it from the power source.
• Locate the Reset Button: Find the CMOS reset button on the motherboard. It’s usually labelled and sometimes backlit.
• Press and Hold the Button: Press and hold the reset button for about 5-10 seconds.
• Power On the Computer: Plug your PC back in and power it on to see if that assisted/did the trick.