What resetting your BIOS means and when you need to do it

Resetting your BIOS to default settings restores the firmware that controls your hardware back to the manufacturer's original configuration. Your BIOS (Basic Input/Output System) is the software that runs before your operating system loads — it manages things like boot order, fan speed, and power settings. Most of the time you never touch it and don't need to.

You might reset your BIOS if your computer won't start, if you've changed settings and now something doesn't work, or if you're troubleshooting a hardware problem. A reset clears any custom settings you or someone else made, which can fix issues caused by those changes. It does not delete your files, your operating system, or your programs — it only affects the firmware layer underneath.

A reset is different from a BIOS update. Updating installs new firmware from the manufacturer. Resetting goes back to whatever version you already have. If you're not sure whether you need a reset or an update, a reset is the safer first step.

Key Takeaways

  • Resetting your BIOS clears custom hardware settings but does not touch your files, programs, or operating system.
  • The exact steps depend on your computer's manufacturer — Dell, HP, Lenovo, and others have different BIOS menus and key combinations.
  • You enter the BIOS by pressing a specific key (often Delete, F2, or F10) during startup, before Windows or your operating system loads.
  • If you cannot get into the BIOS because your computer won't start, you may need to remove the CMOS battery from the motherboard as a last resort.
  • Write down any custom settings before you reset, in case you need to reconfigure them afterward.

How to enter your BIOS menu

To reset your BIOS, you first have to get into the BIOS menu itself. This happens during the startup process, before your operating system loads. You do this by pressing a specific key repeatedly as soon as you turn on the computer.

The key varies by manufacturer. For most computers it is Delete, F2, F10, or F12. Some Dell machines use F2, some use Delete. HP and Lenovo often use F2 or F10. Asus uses Delete. The correct key is usually shown on the startup screen for a fraction of a second — look for text that says "Press [key] to enter Setup" or "Press [key] for BIOS."

If you miss the window, restart the computer and try again. You have only a few seconds. If you're not sure which key your computer uses, look up your specific model number online — search "[your computer brand and model] enter BIOS" and you'll find the right key. Once you press it, the BIOS menu will open and you can navigate using your keyboard.

Finding the reset option in your BIOS menu

Once you're in the BIOS menu, look for an option to reset to defaults. The exact name and location varies. Common names are "Reset to Default," "Load Defaults," "Restore Defaults," "Load Optimized Defaults," or "Clear CMOS." Some manufacturers put this in an "Exit" menu, others in "Tools," and some in "Advanced."

Use your keyboard arrow keys to navigate the menu. Read the menu items carefully — you're looking for anything with the word "default" or "reset" in it. When you find it, select it and confirm. The BIOS will ask you to confirm that you want to reset — this is a safety step. Say yes, and the reset will happen when ready.

After the reset, the BIOS will usually ask whether you want to save and exit, or just exit. Choose "Save and Exit" so the default settings are written to your firmware. Your computer will then restart and boot normally into your operating system.

What to do if you cannot enter the BIOS

If your computer won't start at all, or if it starts but you cannot get into the BIOS menu no matter which key you press, you may need to reset the CMOS battery. The CMOS is a small battery on the motherboard that stores BIOS settings. Removing it for a few minutes clears those settings and resets the BIOS to factory defaults.

To do this, you must open your computer's case. Shut down the computer completely and unplug the power cable. Open the case according to your computer's manual — this usually means removing a side panel held by screws. Look for a small coin-shaped battery on the motherboard, usually silver and about the size of a dime. Note its position, remove it gently, wait 30 seconds, and reinstall it in the same orientation.

This method works on most desktop computers. Laptops are harder to open and the CMOS battery may not be accessible without professional help. If you're not comfortable opening your computer, or if you cannot find the battery, take your computer to a repair shop rather than risk damaging something inside.

Reconfiguring settings after a reset

After a reset, your BIOS is back to factory defaults, but you may need to adjust a few things before everything works the way it did before. The most common issue is boot order — the BIOS may no longer be set to boot from your hard drive first, which means your computer might try to boot from a USB drive or DVD instead.

If your computer boots normally into Windows or your operating system, you're done. If it doesn't, go back into the BIOS and check the boot order. Set your main hard drive (usually labeled as "SATA" or with your drive's brand name) to be first in the boot sequence. Save and exit again.

If you had changed other settings before the reset — like fan speeds, RAM timing, or power management — those will now be back to defaults. Most users don't need to change these. If you remember what you changed and why, you can go back in and adjust them again. If you're not sure, leave them at defaults — that's the safest configuration.

Differences between manufacturers

Dell computers usually show "Press F2 for Setup" during startup. Once in the BIOS, look for "Reset to Default" in the Exit menu. HP and Compaq machines often use F10 and put the reset option in a Tools or File menu. Lenovo ThinkPads use F1 or F2 and may label it "Reset to Default Values" or "Load Default Settings."

Asus desktop and gaming computers use Delete to enter the BIOS and usually have a "Load Optimized Defaults" option in the Exit menu. MSI boards often use Delete as well and put the reset in the main menu or under "Settings." If you're building a custom PC or have a less common brand, your motherboard manual will have the exact steps.

The underlying process is the same across all of them — enter the BIOS, find the reset option, confirm, save, and exit — but the menu names and key combinations do vary. When in doubt, search your specific model number and "reset BIOS" to find the exact steps.

When a BIOS reset doesn't solve the problem

If your computer still won't start or still has the same problem after a reset, the issue may not be in the BIOS. Hardware failures, corrupted operating system files, or failing hard drives can look like BIOS problems but won't be fixed by a reset.

If the computer boots into Windows but is running slowly or crashing, a BIOS reset alone won't help. Go back to the category you came from — "How to Keep Your Computer Running Smoothly and Fast" — for steps on cleaning up your operating system, checking for malware, and freeing up disk space. Those are more likely to be the cause.

If you've reset the BIOS and the computer still won't start, or if you're not comfortable opening your computer to remove the CMOS battery, contact a local repair shop. They can diagnose whether the problem is in the firmware, the hardware, or the operating system.

Frequently Asked Questions

Will resetting my BIOS delete my files or programs?

No. Your BIOS is firmware that runs before your operating system loads. Resetting it does not touch your hard drive, your files, your programs, or Windows. It only clears the settings that control your hardware.

What if I reset my BIOS and now my computer won't boot?

Go back into the BIOS and check the boot order. Make sure your main hard drive is listed first. If it is and the computer still won't boot, the problem may be something other than the BIOS — try booting from a Windows recovery disk or contact a repair shop.

How long does a BIOS reset take?

The reset itself takes a few seconds. Entering the BIOS, finding the reset option, and confirming usually takes a few minutes. Your computer will restart normally after the reset is complete.

Can I undo a BIOS reset if I change my mind?

Not directly. Once you reset, the custom settings are gone. If you wrote down your previous settings before the reset, you can go back in and reconfigure them manually. This is why it's a good idea to note any custom settings before you reset.

Is it safe to reset my BIOS?

Yes. Resetting to defaults is one of the safest troubleshooting steps you can take. The worst that can happen is that your computer boots into your operating system normally, and you've solved nothing — but you haven't broken anything either.