How to Access BIOS & UEFI on Any Laptops and PCs

You've tried several things to improve your laptop or desktop PC's performance—deleting unnecessary files, uninstalling unused programs, and even defragging the hard drive. But it turns out the real problem is a virus. You might think of installing antivirus software, but it doesn't seem to fix the issue.

Your last option is to reinstall Windows. The only problem is, your computer doesn’t have a DVD drive. So, you’ll need to reinstall Windows by copying the installation files to a flash drive and making it bootable.

To manually reinstall Windows using a bootable flash drive, you'll have to enter the BIOS or UEFI to adjust one small setting: making the flash drive the first thing your laptop checks when it boots up.

If you're not sure how to get into BIOS or UEFI, don't worry! Carisinyal has got you covered with steps that work for different laptop and desktop brands.

What is BIOS?

Without BIOS, a computer wouldn’t work. BIOS is what starts up all the devices connected to your motherboard, including loading the operating system from your hard drive or SSD (or even a floppy disk back in the old DOS days).

The late Gary Kildall invented BIOS. He first created an operating system to control and monitor microcontroller devices back in 1975. But Kildall later realized his system could also work for more complex devices like computers.

At first, BIOS could only handle one command at a time because it operated on 8 bits. But as technology advanced, BIOS evolved to handle more tasks and became more powerful. IBM loved Kildall’s creation and started using it in their computers in 1981.

Since then, all IBM computers have included BIOS technology, which stands for Basic Input/Output System. Companies like American Megatrends and Phoenix Technology have also adapted IBM’s BIOS to fit the specs of the computers they build.

How BIOS Works

When something goes wrong with your device, the BIOS gives you helpful info, either through sounds or on-screen messages, so you can check what’s causing the issue.

For instance, it might warn you if a cable is loose, the RAM isn't properly connected, or the processor fan isn't working. In these cases, the BIOS prevents the computer from loading the operating system until the issue is fixed.

If everything is working fine, the BIOS moves on to the next step: running the MBR (Master Boot Record). The MBR is located in the first sector of your hard drive and helps launch the operating system.

Besides these checks, the BIOS also stores important information like the time, processor temperature, passwords, and more.

For advanced users, the BIOS provides access to tweak things like voltage and frequency settings for the motherboard and connected devices. This is called overclocking, which helps boost your computer’s speed. The BIOS is stored on a special chip built into the motherboard.

Since the BIOS is rewritable, you can update it without replacing the chip. You just need to install the update while your computer is on. On Android phones, BIOS works similarly to recovery software like TWRP or CWM.

How to Enter BIOS

Different brands of laptops and PCs have their own versions of BIOS, so the way to access it can vary. Even two models from the same brand might not have the same method.

But the general process is the same. The main difference is which key you need to press to access the BIOS, and that varies from computer to computer.

How to Enter BIOS on a Laptop

Let’s use a Dell laptop as an example to show you how to access BIOS. Here’s how to do it:

1. First, restart your laptop. You can do this from the Windows start menu or by pressing the power button if the laptop is off. Then, wait for the laptop to boot up.

2. When you see the Dell logo on the screen, quickly press the F2 key.

3. That's it! You’re now in the BIOS where you can adjust various settings.

Apart from F2, Dell laptops also use the F12 key, which lets you change the boot order (for example, if you want to boot from a hard drive, DVD, or flash drive).

For other laptop brands, the steps are pretty much the same. The only difference is which key you press to enter the BIOS.

For some Toshiba laptops, you need to press and hold the F2 key while the laptop is off, then press the power button to enter BIOS.

Here’s a list of BIOS access keys for different laptop brands:

How to Enter BIOS on a Desktop PC

The process for entering BIOS on a desktop PC is pretty similar to that of a laptop. However, the access keys can vary depending on the BIOS vendor or motherboard brand your PC uses.

Here’s a list of common BIOS access keys based on the BIOS vendor and motherboard brand:

What is UEFI?

If the methods for entering BIOS don’t work, your computer might be using UEFI instead of BIOS. Since around 2010, some laptop manufacturers have switched to UEFI, which stands for Unified Extensible Firmware Interface.

Intel, a California-based processor company, announced that 2020 was the last year they would support BIOS, transitioning fully to UEFI, a more modern system. So why is BIOS being phased out, and what makes UEFI better?

Intel initially developed this system, which was called EFI at first. Then, around 140 companies worldwide, including AMD, ARM, American Megatrends, Microsoft, Lenovo, and HP, formed a forum to work on it together. They all agreed that UEFI could speed up the boot process and modernize the outdated look of BIOS. UEFI also solves many limitations that BIOS has.

For example, UEFI doesn’t rely on the MBR (Master Boot Record) when starting up the operating system, making booting faster. It also shortens the time it takes to wake the computer from hibernation.

UEFI can handle larger partition sizes—over 2 TB—and supports 64-bit device drivers, allowing it to manage up to 17.2 billion GB during startup. It also has a more user-friendly interface, with many customizable features that manufacturers can tweak.

Unlike BIOS, UEFI can be operated using both a keyboard and mouse, making it more flexible. Most computers or laptops released after 2010 support UEFI, but manufacturers usually still include BIOS within the UEFI system.

How to Enter UEFI

Microsoft has fully supported UEFI since the release of Windows 8 in 2012. If you're using Windows 8, 8.1, or 10, you can easily access UEFI through Recovery Mode. Here’s how:

1. Click Start and go to Settings.

2. Scroll to the bottom of the Settings menu and select Update & Security.

3. In the Update & Security tab, click on Recovery (it’s the sixth option).

4. Under Advanced startup, click the Restart now button.

5. Wait for a moment until a new screen appears, then select Troubleshoot.

6. Go to the Advanced options menu,

7. Choose UEFI Firmware Settings.

8. Click Restart, and your UEFI menu will appear shortly.

This is a brief overview of BIOS, UEFI, and how to access them. Interestingly, most BIOS access keys are located in the first row of the keyboard—from Esc to Del—regardless of the computer brand.

So, if you’re unsure about the specific key for accessing BIOS, try pressing any key between Esc and Del. If that doesn’t work and your computer uses UEFI, just follow the steps to enter Recovery Mode as mentioned above.