UEFI vs. BIOS: Which One You Ought to Use

UEFI vs. BIOS, which one is best, and which one it is best to use? It’s a great query for anybody who desires to learn how the underlying {hardware} works in order that they will personalize the nuts and bolts of their private computer systems.


At their cores, UEFI and BIOS are two firmware interfaces for computer systems. The only real function behind them is to behave as interpreters between the working system and the pc firmware. Each are used at startup to initialize the {hardware} elements and cargo the working system onto the onerous drive.

UEFI is newer, higher and is included by default on most trendy PCs. However issues aren’t so simple as them appear. Right here’s a rundown of the functionalities of each methods to assist information you within the choice of UEFI vs. BIOS.

The Fundamentals of BIOS

BIOS (Fundamental Enter-Output System) works by studying the primary sector of the onerous drive with the subsequent system’s tackle to initialize or code to execute. BIOS additionally selects the boot system that must be initialized to begin the working system.

Uefi Vs Bios Comparison 02 Bios Main Menu

Since BIOS has been in use for the reason that Eighties (it’s been round for the reason that MS-DOS period), it nonetheless works in 16-bit mode. This limits the quantity of code that may be learn and executed from the firmware ROM.

To study extra about BIOS, learn up on all of its widespread settings.

Disk Measurement Limitations

One of many greatest factors in UEFI vs. BIOS is that the latter makes use of 32-bit entries in its partition desk. This limits the overall bodily partitions in BIOS to solely 4.

Uefi Vs Bios Comparison 03 Mbr Sample Layout

Additional, every of those 4 partitions can solely have as much as 2TB in total dimension, so the BIOS can solely boot from a drive with a bodily house of two.2TB. This may be limiting for methods that use greater capability drives for redundant storage.

BIOS Velocity and Efficiency

As mentioned above, BIOS works seamlessly in older 16-bit methods. BIOS builders design the system to be each light-weight and easy to make it extremely fast and responsive – even in slower machines.

For instance, a conventional BIOS machine that skips reminiscence and {hardware} checks can load its working system in a single to 2 seconds.

The Fundamentals of UEFI

In contrast to BIOS, UEFI (Unified Extensible Firmware Interface) shops the entire details about system initialization in an .efi file as a substitute of a devoted chip. This file is usually saved on the onerous drive inside a particular partition known as EFI System Partition (ESP). ESP additionally incorporates the boot loader applications for the working system put in on the pc.

Uefi Vs Bios Comparison 06 Efi Folder Present

UEFI is supposed to fully exchange BIOS and usher in many new options and enhancements that may’t be carried out by BIOS.

Tip: discover ways to boot straight into UEFI in Home windows 10.

Breaking Out of Measurement Limitations

One of many greatest benefits UEFI over BIOS is that it’s doable to incorporate bigger capability drives. In contrast to the normal BIOS Grasp Boot File, the UEFI GUID Partition Desk makes use of 64-bit entries, so you possibly can dramatically lengthen assist for dimension prospects of the onerous drive. (Extra on distinction between MBR and GPT).

Uefi Vs Bios Comparison 07 Sample Efi Partition Layout

As well as, UEFI helps bigger HDDs and SSDs. UEFI’s theoretical dimension restrict for bootable drives is greater than 9 zettabytes, whereas BIOS can solely boot from drives 2.2 terabytes or smaller.

UEFI Velocity and Efficiency

Since UEFI is platform impartial, it might be able to improve the boot time and velocity of the pc. That is particularly the case when you’ve got massive onerous drives put in in your laptop. This enhancement is dependent upon how UEFI is configured to run.

UEFI also can carry out higher whereas initializing the {hardware} units. Usually, this velocity enhancement is a fraction of the overall boot time, so you’ll not see an enormous distinction in total boot time. Builders could make use of the UEFI shell surroundings, which might execute instructions from different UEFI apps, optimizing the efficiency of the system additional.

UEFI Safety

Safe boot is a characteristic of UEFI that has been carried out in Home windows 8 and has grow to be the usual for Home windows 11. The largest good thing about UEFI is its safety over BIOS. UEFI can enable solely genuine drivers and companies to load at boot time, ensuring that no malware could be loaded at laptop startup.

Uefi Vs Bios Comparison 08 Uefi Boot Diagram

Microsoft carried out this characteristic to counter piracy points in Home windows, whereas Mac has been utilizing UEFI for fairly a while. Safe Boot works by requiring a digital signature of boot loaders, which ought to require digital signature by the kernel. This course of continues till the working system is began. This safe boot characteristic can be one of many the reason why it’s harder to put in one other working system on a Home windows machine.

BIOS Safety vs. UEFI

One of many greatest disadvantages of BIOS is its lack of correct firmware safety. It’s doable to lock down a BIOS machine by a boot password. Nevertheless, this strategy doesn’t shield you from arbitrary code execution.

Uefi Vs Bios Comparison 04 Data Execution Prevention

Whereas newer BIOS machines provide Knowledge Execution Prevention modules, this mechanism doesn’t assist iterative driver execution within the firmware stage. As such, utilizing BIOS could be a problem if you wish to correctly safe your laptop.

Why Select UEFI?

One purpose to decide on this over the extra acquainted BIOS is that Intel now not helps the “conventional” BIOS in 2022.

Uefi Vs Bios Comparison 09 Windows Safe Boot Uefi

UEFI gives the next performance and benefits:

  • Languages: BIOS is written in assembler, whereas UEFI is written in less complicated C-language.
  • Drives: UEFI helps bigger HDDs and SSDs. UEFI’s theoretical dimension restrict for bootable drives is greater than 9 zettabytes, whereas BIOS can solely boot from drives 2.2 terabytes or smaller.
  • Drivers: UEFI has intricate but discrete drivers, whereas BIOS makes use of drivers in non-compulsory ROM (read-only reminiscence). With BIOS, updating the {hardware} requires retuning the ROMs for compatibility. This specification applies to separately-written, upgradable UEFI drivers.
  • Boot time: most often, UEFI gives a sooner booting time vs. BIOS machines.
  • Safety: UEFI provides improved security measures. “Safe Boot” prevents the pc from booting from unsigned or unauthorized purposes. The OS should include a recognizable key. With out Safe Boot enabled, a PC is susceptible to malware corrupting the startup course of.
  • Knowledge processors: UEFI runs in 32-bit or 64-bit mode. BIOS runs solely in 16-bit mode and will make the most of only one MB of executable reminiscence.
  • GUI: UEFI gives a extra intuitive graphical person interface that you could be navigate with a mouse and keyboard, in contrast to BIOS.

One other benefit of UEFI is that an industry-wide interface discussion board maintains it and is extra manufacturer-agnostic than BIOS.

Why Select BIOS?

Some causes a person could select Legacy BIOS as a substitute of UEFI embrace:

  • BIOS is right if you happen to don’t require effective management over how your laptop operates.
  • BIOS can be adequate if you happen to solely have small drives or partitions. Though many more moderen onerous drives exceed BIOS’s 2-terabyte restrict, not each person requires that quantity of house.
  • UEFI’s “Safe Boot” characteristic could lead to OEM producers stopping customers from putting in different working methods on their {hardware}. Should you stick to BIOS, you sidestep this problem.
  • BIOS gives entry to {hardware} info within the interface, whereas not each implementation of UEFI does so. {Hardware} specs are accessible throughout the OS, nevertheless.

Some newer PCs can help you run UEFI in Legacy BIOS Mode. Customers who want to preserve machines working older working methods, together with Home windows 7, will wish to allow this characteristic.

Ceaselessly Requested Questions

How can I verify whether or not I’m utilizing UEFI or BIOS?

You possibly can simply verify whether or not you’re working in BIOS or UEFI mode by clicking “Begin,” trying to find “system info,” then underneath “System Abstract” within the left pane wanting over to “BIOS Mode” on the suitable aspect. UEFI means UEFI (clearly), whereas “Legacy” means “BIOS” (rather less clearly).

In Linux, you are able to do this by opening a terminal window and working ls /sys/firmware/efi. It will listing the UEFI information and folders which can be current in your distribution. Working this command in a BIOS machine will yield no outcomes.

Is UEFI higher than BIOS?

As you might have labored out, UEFI is the one to make use of most often. It supposedly has sooner boot occasions, can run in as much as 64-bit mode, and is usually extra superior in its options and partitioning prospects than BIOS. After all, when you’ve got an historic PC that solely runs BIOS, you then’ll have to improve your motherboard or PC to profit from UEFI.

Can I convert BIOS to UEFI?

Now that you recognize that UEFI is the best way to go most often, you most likely wish to change over to it, proper? You possibly can, relying on a number of components! There are a couple of steps and some issues to think about.

You are able to do this conversion straight by Home windows 10, although it’s doable chances are you’ll want to change from “Legacy BIOS” to UEFI by your motherboard’s BIOS settings (accessed by repeatedly hitting F8, F2 or Del (often) as your laptop is booting up.

How do I replace my UEFI (or BIOS)?

Updating the UEFI (or BIOS) is a giant choice that’s advisable if you would like the newest options and the motherboard aspect of stuff working optimally, however you possibly can have extreme penalties in case your PC crashes throughout a BIOS replace or fails one other approach.

Extra trendy motherboards allow you to replace the BIOS straight by the BIOS (accessed as your PC is booting up), whereas on laptops the updates are likely to occur mechanically.

With older motherboards, you might have to go to the motherboard producer’s web site, obtain the proper BIOS model for the proper motherboard to a flash drive, then insert the flash drive into your PC and reboot your PC. It ought to then boot to the flash drive and the BIOS replace course of.

Picture credit score: Unsplash. All alterations and screenshots by Ramces Purple.