What is UEFI? How to access it!!

UEFI is the abbreviation of Unified Extensible Firmware Interface, which is a firmware interface for computers and it works as a "middleman" to connect a computer's firmware to its operating system. It is used to initialize the hardware components and start the operating system stored on the hard disk drive when the computer starts up.

UEFI possesses many new features and advantages that cannot be achieved through the traditional BIOS and it is aimed to completely replace the BIOS in the future.

UEFI stores all the information about initialization and startup in a .efi file, a file stored on a special partition called EFI System Partition (ESP). The ESP partition will also contain the boot loader programs for the operating system installed on the computer.

It is because of this partition, UEFI can directly boot the operating system and save the BIOS self-test process, which is an important reason for UEFI faster booting.

Note: Some computer users use UEFI boot but still refer to it as the “BIOS”, which may confuse some people. Even if your PC uses the term “BIOS”, most modern PCs you buy today use UEFI firmware instead of a BIOS. To distinguish UEFI and BIOS, some also call UEFI firmware as UEFI BIOS, and BIOS is called Legacy BIOS or traditional BIOS.

How to Access to UEFI Windows 10

When you need to perform a clean install or repair Windows 10 boot issue, people always tell you that you need to go to the BIOS to change the bootup settings, giving the USB drive or CD/DVD boot sequence priority. If your computer is using UEFI firmware, how do you get into the UEFI Windows 10?

If you want to access UEFI Windows 10, you don't need to press a key while your computer starts as computers equipped with UEFI now boot very fast and you only have very limited time to do it. So you can try the following steps to access UEFI Windows 10.

Step 1. Right-click the Windows Start menu and choose Settings. Then, choose Update and Security.

Step 2. At this interface, select Recovery. At the Advanced startup section, click Restart now. Then the system will restart.

Step 3. Click Troubleshoot.

Step 4. Choose Advanced options to get into the next page.

Step 5. After that, select UEFI Firmware Settings.

Step 5. Click Restart to restart the system and enter UEFI interface.

Different PCs with UEFI will have different interfaces and features. It’s determined by your PC manufacturer, but the basics will be the same on each PC.

UEFI FAQ 

???? What is the difference between UEFI and BIOS?

BIOS and UEFI are two firmware interfaces for computers to start the operating system. BIOS uses the Master Boot Record (MBR) to save information about the hard drive data while UEFI uses the GUID partition table (GPT). Compared with BIOS, UEFI is more powerful and has more advanced features. It is the latest method of booting a computer, which is designed to replace BIOS. In brief, UEFI is the successor to BIOS.

???? Should I use UEFI or BIOS?

Nowadays, UEFI gradually replaces the traditional BIOS on most modern PCs as it includes more security features than the legacy BIOS mode and also boots faster than Legacy systems. If your computer supports UEFI firmware, you should convert MBR disk to GPT disk to use UEFI boot instead of BIOS. However, if you're booting from a network that only supports BIOS, you'll need to boot to legacy BIOS mode.

???? What is UEFI boot mode?

UEFI boot mode refers to the boot process used by UEFI firmware. UEFI stores all the information about initialization and startup in an .efi file that is saved on a special partition called EFI System Partition (ESP). During the POST procedure, the UEFI firmware scans all of the bootable storage devices that are connected to the system for a valid GUID Partition Table (GPT).

The UEFI firmware scans the GPTs to find an EFI Service Partition to boot from. If the EFI bootable partition is not found, the firmware may revert to the old Legacy Boot method. If both UEFI boot and Legacy boot fail, you may receive the disk boot failure error message. 

???? What is the advantage of UEFI boot?

UEFI boot has many advantages BIOS mode. For example, UEFI Supports unlimited number of partitions, and support the disk which is larger than 2 TB. Computers that use UEFI firmware can boot faster than BIOS, as no magic code must execute as part of booting. UEFI also has more advanced security features such as secure startup, which helps to keep your computer more secure.