How to enter BIOS on your computer

To access your computer's BIOS (Basic Input/Output System), you restart your computer and press a specific key during startup—before Windows or your operating system loads. The key varies by manufacturer: on most Dell, Lenovo, and HP machines it is F2 or Delete; on Asus and MSI boards it is often Delete or F2; on Apple computers running macOS there is no traditional BIOS, but you can access firmware settings by restarting and holding Command+Option+P+R. You have only a few seconds to press the key, so you may need to restart and try again if you miss the window.

The exact key appears briefly on your screen during startup, usually in the bottom corner or as a prompt that says "Press [key] to enter Setup" or "Press [key] for BIOS." If you do not see it, restart and watch carefully, or check your computer's manual or manufacturer website for your specific model. Once you press the key in time, your computer will load the BIOS menu instead of your operating system.

Key Takeaways

  • You enter BIOS by restarting your computer and pressing a key (usually Delete, F2, or F12) during the startup sequence, before Windows loads.
  • The correct key depends on your computer's manufacturer and motherboard model, and it appears on screen during startup.
  • BIOS controls hardware settings like boot order, fan speed, and RAM detection, but changing the wrong setting can prevent your computer from starting.
  • Most people only need to access BIOS to change the boot order or enable hardware features; everyday computing does not require BIOS changes.
  • If you are unsure what a setting does, do not change it; write down the original values before making any adjustments.

Why you might need to access BIOS

BIOS is the firmware that runs before your operating system starts. It controls which hard drive or USB device your computer boots from, how fast your fans spin, whether certain hardware ports are turned on or off, and how much RAM your system recognizes. Most of the time you never need to touch BIOS—your computer works fine with the factory defaults.

You may need to enter BIOS if you are installing a new hard drive and your computer does not recognize it, if you want to boot from a USB drive to install Windows or run a repair tool, if a hardware component is not showing up in Windows, or if you need to enable a feature like virtualization for software development. Some older computers also require BIOS changes to enable USB 3.0 ports or to adjust fan speeds if your machine is overheating.

Step-by-step: entering BIOS on Windows computers

Shut down your computer completely. Press the power button to turn it on. As soon as the screen lights up, begin pressing your BIOS key repeatedly—do not wait for the Windows logo to appear. On most machines you have between two and five seconds. If you see the Windows login screen, you waited too long; shut down and try again.

When you press the key in time, your screen will show a dark menu with white or blue text. This is the BIOS interface. You navigate using arrow keys on your keyboard; Enter selects an option, and Escape or a specific key (usually shown at the bottom of the screen) exits a menu. Take your time reading the menus—BIOS does not time out and close on its own, so you can explore without rushing.

Before you change anything, write down the current settings you see. If something goes wrong, you can restart and change them back. When you are done making changes, look for a "Save and Exit" or "Exit and Save Changes" option, usually near the bottom of the main menu. Select it and confirm when prompted. Your computer will restart and load Windows normally.

Accessing BIOS on Mac computers

Apple computers do not have a traditional BIOS menu like Windows machines. Instead, they use firmware settings (on newer Macs with Apple Silicon chips) or EFI (on older Intel-based Macs). On a Mac with an Apple Silicon chip (M1, M2, M3, or newer), shut down the computer, press and hold the power button until "Loading startup options" appears on screen, then click "Options" to access firmware settings.

On older Intel-based Macs, shut down the computer, turn it back on, and when ready hold Command+Option+P+R until you hear the startup sound twice or the Apple logo appears and disappears twice. This resets the NVRAM (non-volatile RAM), which stores some of the same settings as BIOS on Windows machines. If you need to change specific firmware settings on an Intel Mac, restart and hold Command+Option+R to enter Recovery Mode, then use the Utilities menu.

Common BIOS settings and what they do

Boot Order tells your computer which drive to start from first. If you have a USB drive plugged in and want to boot from it, you move USB to the top of the list. find Boot is a security feature that prevents unsigned software from loading during startup; you may need to disable it to install certain Linux distributions or older operating systems. Fast Boot speeds up startup by skipping some hardware checks; disabling it can help if your computer is not recognizing a new hard drive.

XMP or DOCP (on AMD systems) enables your RAM to run at its rated speed instead of a slower default; enabling it can improve performance if you have high-speed memory. Virtualization (VT-x on Intel, SVM on AMD) is needed for virtual machines and some development tools. Fan Control lets you adjust how aggressively cooling fans spin; the default is usually "Auto," which is fine for most users. Integrated Graphics can be disabled if you have a dedicated graphics card and want to save power.

What to do if you cannot access BIOS

If you are pressing the key and nothing happens, the most common reason is timing—you are pressing it too late, after Windows has already started loading. Try restarting and pressing the key as soon as the screen turns on, before any logos appear. If that does not work, try holding the key down continuously instead of tapping it.

On some newer computers, especially those with fast SSDs, the startup sequence is so quick that the BIOS prompt flashes too fast to see. In that case, you can restart Windows and hold Shift while clicking the restart button; this brings up the Windows boot menu, which includes an option to restart into firmware settings. On Windows 11, you can also go to Settings > System > Recovery and click "Restart now" under "Advanced startup," then select "Troubleshoot" > "Advanced options" > "UEFI Firmware Settings."

If you still cannot access BIOS and you need to change a setting urgently, contact your computer manufacturer's support line or visit their website for your specific model number. They can walk you through the process or tell you if there is a hardware issue preventing BIOS access.

When to call a professional instead

If you are not certain what a BIOS setting does, do not change it. Changing the wrong setting can prevent your computer from starting, and you may need professional help to reset it. If you are trying to fix a hardware problem and BIOS access is part of the solution, but you are uncomfortable navigating the menus, a local computer repair shop can make the change for you in 15 minutes for a small fee.

If your computer will not start at all and you suspect a BIOS problem, do not keep restarting it repeatedly—you may make the situation worse. Take it to a professional or contact the manufacturer. If you are building a custom computer or installing specialized hardware, the documentation that came with your motherboard will have detailed BIOS instructions; follow those rather than guessing.

Frequently Asked Questions

What is the difference between BIOS and UEFI?

UEFI (Unified Extensible Firmware Interface) is the modern replacement for BIOS. It does the same job but with a better interface and more features. Most computers made after 2010 use UEFI, though the menus look and work almost identically to older BIOS. You access UEFI the same way—by pressing a key during startup.

Can I damage my computer by changing BIOS settings?

You can prevent your computer from starting if you change the wrong setting, but you cannot permanently damage the hardware. If something goes wrong, you can restart and change the setting back. If you get stuck, most BIOS menus have a "Load Defaults" or "Reset to Factory Settings" option that undoes all your changes.

Why does my computer not recognize my new hard drive?

A new drive may not show up in Windows because BIOS does not recognize it yet. Restart into BIOS and look for a menu called "Storage," "Integrated Peripherals," or "Onboard Devices." Make sure the port your drive is plugged into is enabled. If the drive still does not appear, it may be a hardware compatibility issue or the drive may be faulty.

Is it safe to enable XMP in BIOS?

Yes, XMP (Intel) and DOCP (AMD) are safe to enable if your motherboard and power supply support them. They straightforward let your RAM run at the speed it was designed for. If enabling XMP causes instability, you can disable it and go back to the default speed. Most modern systems handle XMP without any problems.

How do I reset BIOS to factory settings?

In the BIOS menu, look for an option called "Load Defaults," "Reset to Defaults," "Restore Factory Settings," or "Load Optimal Defaults." Select it and confirm. Your computer will restart with all original settings restored. This is useful if you made changes and your computer is not working properly.