UEFI vs BIOS | The Core Differences between Them

Share on:

So you may have heard the BIOS and UEFI acronyms tossed around, particularly when you try to turn operating systems or overclock. BIOS and UEFI are two firmware interfaces that operate between the operating system and device firmware for computers. At device initialization, both of these interfaces are used to initialize hardware components and to launch the hard drive operating system. This article can help you consider between UEFI vs BIOS.

You should be aware of what the following acronyms mean (the Unified Extensible Firmware Interface and the Basic Input/Output System). However, have you ever wondered what UEFI vs BIOS are, how they are related to computers and PCs, how the computers are used, and what the differences are between UEFI vs BIOS?

We know your concern and that is why let these terminologies and their interpretations now be demystified.



The Basic Input / Output System is short for BIOS, also known as System BIOS, ROM BIOS, or PC BIOS. Its firmware is integrated into the chipset of the computer. On the PC’s chipset, BIOS firmware is preinstalled. It is a non-volatile firmware that does not remove or alter the configuration even after power off. It is a program that lives in a chip on the motherboard of your machine.

The BIOS loads at boot time and the BIOS is responsible for waking up the hardware of your machine and ensuring it is working properly, then runs the bootloader which boots Windows or any other operating system you have enabled.

The BIOS configuration screen allows you to customize different configurations. There are settings like the hardware setup of your device, machine time, and boot sequence. You will use the button — different on different machines, but usually on Esc, F2, F10 or Delete — to enter the screen when the machine boots. It is stored on the memory of your motherboard itself when you save an environment. The BIOS configures the saved settings for your PC when you restart your device.

The BIOS configuration screen

Before booting the operating system, the BIOS passes through a POST or Power-On Self Test. It verifies the validity and correct running of your hardware setup. You’ll view an error message or hear a vague collection of beep codes if something’s incorrect. In the program manual, you could look up what various series of beeps signify.

As the machine boots and after the POST ends, the BIOS searches for a Master Boot Record, or MBR, which is placed on the boot and is used to boot the bootloader.

The acronym for the complementary metal-oxide-semiconductor can also be used here. The BIOS saves different settings on your motherboard in the battery-backed memory. This is currently no longer true, as this approach was substituted in contemporary systems with flash memory (also known as EEPROM).


UEFI is the abbreviation of a Unified Extensible Firmware Interface (Unified Extensible Firmware Interface), the firmware interface for computed devices. It is used to start the hardware components and run the hard drive operating system at boot time.

UEFI has several new characteristics and benefits which cannot be accomplished by the traditional BIOS and it aims to eliminate the BIOS completely in the future.

UEFI stores all configuration and start-up information in a .efi file which is located on an EFI System Partition partition (ESP). Often in the ESP partition are boot loader applications loaded on the device for the operating system.

Some machine users use UEFI but also call it “BIOS,” which may make some people feel confused. And if your PC uses ‘BIOS,’ you use UEFI firmware instead of a BIOS on the newest PCs you purchase now. 


Some name UEFI firmware UEFI BIOS to differentiate UEFI and BIOS, while BIOS is named Legacy BIOS or conventional BIOS.

This partition makes it possible for UEFI to boot the operating system directly and to save the self-testing phase for BIOS, a key explanation for faster UEFI booting.

Differences Between UEFI vs BIOS

The BIOS has not changed a lot, though it has been around for a long time. At the time of MS-DOS Cs of the 1980s, even those PCs had a BIOS!

Naturally, over time, the BIOS has matured and changed. Certain extensions including ACPI, Advanced Settings, and Power Interface have been created. This makes it easier for the BIOS to customize machines and implement sophisticated power management features, such as sleep. But since the days of MS-DOS, the BIOS has not progressed or changed much like other PC technologies.

The standard BIOS remains severely limited. UEFI would replace BIOS entirely and introduce a number of new functionality and improvements which can’t be carried out through BIOS. UEFI has been planned to solve all of the old BIOS’ shortcomings. There are variations between the two thus. Let’s go one by one around the gaps.


The BIOS firmware is written in the assembly language, while the UEFI firmware is written in simplified C-language.


UEFI is supported by bigger HDDs and SDDs. UEFI has more than nine zettabytes of possible size cap for bootable drives while BIOS will boot only with 2.2 or smaller drives. 

The BIOS limitations are avoided by this new standard. UEFI will boot from larger than 2.2 TB or drives – indeed, the 9.4 zettabytes theoretically. The average scale of all data on the Internet is about three times. It’s since UEFI uses instead of MBR the GPT partitioning mechanism. It also standardizes the boots by starting EFI executables instead of executing code from the master boot drive record.


UEFI uses drivers that are intricate yet discrete, while BIOS uses drivers that are stored in choice ROM (read-only memory). Updating the hardware with BIOS necessitates re-tuning the ROMs for reliability. This specification extends to UEFI drivers that are separately published and upgradeable.


UEFI-enabled computers boot quicker than BIOS-enabled computers. Various UEFI optimizations and enhancements will make the system boot faster than ever.


UEFI can be operated in 32-bit or 64-bit mode and has much more addressable access space in comparison with BIOS. It also ensures that UEFI configuration screens can be more slick, like graphs and mouse cursor assistance, than BIOS settings screens. This is not obligatory, though. Many PCs still feature UEFI text mode settings that look like an old BIOS screen.

Security Process

Other functionalities are abundant in UEFI. It provides Secure Boot, which ensures that the operating system’s authenticity can be tested to guarantee that no malware has meddled with the boot operation. It will support networking functionality directly in the UEFI firmware, allowing for remote troubleshooting and setup. To set up a standard BIOS, you must be seated in front of a physical device.

Graphical User Interface

Unlike BIOS, UEFI has a more intuitive interactive user interface that can be navigated using a mouse and keyboard.

Another benefit of UEFI is that it is maintained by an industry-wide interface forum and is more manufacturer-agnostic than BIOS.

As UEFI has a lot of desired facilities and advantages, you will go for UEFI. Nowadays, UEFI is increasingly replacing conventional BIOS on most new PCs since it has more protection features than legacy BIOS mode and boots quicker than Legacy systems. If your machine supports UEFI firmware, you can upgrade an MBR disk to a GPT disk so that you can use UEFI instead of BIOS to boot. If you’re booting from a network that only supports BIOS, you’ll have to boot into legacy BIOS mode. So for this, your machine needs to support UEFI.


While all modern computers come standard with UEFI, there are a few explanations why you may choose BIOS over UEFI:

If you’re a novice who doesn’t want to play with some kind of firmware, BIOS is the way to go.

If you have more than 2 TB per hard disk or partition, you will use BIOS.

BIOS enables the use of various operating systems without the need to change any configurations. From a modern perspective, this could be a protection problem, but sure, no hassles for the customer.

The BIOS interfaces with the operating system to provide system detail. As a result, if the operating system operates in 16-bit mode, you won’t need to write code to communicate with the hardware. It may use BIOS-provided methods directly. Otherwise, whenever the operating system moves to 32bit or 64bit mode, it must have its own subroutines for communicating with the hardware.

If you choose a keyboard and text-based UI to mouse and GUI navigation, BIOS is for you.

UEFI recognizes these shortcomings and offers a Legacy mode. It allows you to run anything as though it were BIOS firmware. However, bear in mind that Intel has stated that standard BIOS will no longer be supported after 2020.

Different UEFI-enabled PCs will have different interfaces and features. It is all up to the maker of the PC, but the basics would remain the same on each PC.

Now it is up to you what to do with your pc or laptop. Here you have got the answer. In the end, thank you for coming to this article and now we hope that you know all about the differences between UEFI vs BIOS.

About The Author

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.