Check if your PC uses UEFI or BIOS

Long time Windows users might be well aware of the term – UEFI. For those who are not, UEFI is the abbreviated form of Unified Extensible Firmware Interface, a sort of BIOS replacement to set up the hardware and load and start an operating system. It was first introduced by Intel as Intel Boot Initiative which was later changed to EFI. Later, EFI was then taken over by the Unified EFI Forum and was therefore named as UEFI. UEFI comes with a boot manager which removes the needs for a separate boot loader. Besides, it gives you faster start-ups and better networking support. Most recent Windows PCs are shipped with UEFI support. To check if your PC supports and uses UEFI/EFI or BIOS, follow the steps highlighted below.

Check if your PC uses UEFI or BIOS

(1) Open File Explorer and navigate to the following folder: C:\Windows\Panther.


In the folder named Panther you will see a text file titled setupact.log. The file will automatically open in Notepad.

setup act

Once you have opened setupact.log, click Ctrl+F to bring up the Find box and search for an entry named Detected Boot Environment.


Once you find Detected Boot Environment, you will notice the words BIOS or UEFI mentioned as follows:

Callback_BootEnvironmentDetect: Detected boot environment: BIOS


Callback_BootEnvironmentDetect: Detected boot environment: UEFI


If your PC supports and uses UEFI, the word UEFI will appear, else BIOS. (2) Alternatively, you can also open Run, type MSInfo32 and hit Enter to open System Information. uefi or bios If your PC uses BIOS, it will display Legacy. If it is using UEFI, it will display UEFI! If your PC supports UEFI, then if you go through your BIOS settings, you will see the Secure Boot option.

In general, UEFI-enabled machines have faster startup and shutdown times as compared to BIOS-based machines. Here is a list of Windows 10 features that requires UEFI:

  • Secure Boot protects Windows 10 pre-boot process against bootkit and other malware attacks.
  • Early Launch Anti-malware (ELAM) driver gets loaded by by Secure boot first and checks all non-Microsoft drivers before they are loaded.
  • Windows Trusted Boot protects the kernel and system drivers during launch.
  • Measured Boot will measure components from firmware till the boot start drivers & stores these measurements in the TPM chip.
  • Device Guard uses CPU virtualization and TPM support to support Device Guard with AppLocker, and Device Guard with Credential Guard.
  • Credential Guard works with Device Guard and uses CPU virtualization and TPM support to protect security information like NTLM hashes, etc.
  • BitLocker Network Unlock will automatically unlock Windows 10 at reboot when connected to a corporate network.
  • GUID Partition Table or GPT disk partitioning is required to enable large boot disks.

Hope this helps.

Posted by on , in Category Windows with Tags
Anand Khanse is the Admin of, a 10-year Microsoft MVP Awardee in Windows (2006-16) & a Windows Insider MVP. Please read the entire post & the comments first, create a System Restore Point before making any changes to your system & be careful about any 3rd-party offers while installing freeware.