How to configure UEFI boot in a BIOS that supports UEFI and Legacy boot modes?

Overview:

Industrial mini computers are widely used, and to ensure good compatibility, BIOS in Intel 10th generation and earlier product lines typically support two boot modes: UEFI and Legacy. Sometimes, it's necessary to configure UEFI-only boot mode in the BIOS, especially when installing a newer version of the operating system. Here's how to do it:

Note that when setting UEFI boot mode in the BIOS:

1. After enabling UEFI boot mode, the corresponding partition type should be GPT partition.
2. After setting UEFI boot mode, it's essential to use tools that support UEFI boot. Here's a guide on how to create UEFI bootable installation media (using Windows 11 as an example): How to Create Windows 11 Installation Media

UEFI Mode Boot Process: UEFI is used to automatically load the operating system from a pre-booted environment to save boot time.

UEFI Mode Boot Process:

1. Upon turning on the computer, it undergoes a power-on self-test and loads UEFI firmware, which initializes the hardware required for startup.
2. UEFI firmware locates the EFI partition boot file (efiMicrosoftbootbootmgfw.efi) boot manager.
3. The boot manager reads the BCD file (efiMicrosoftBCD) from the EFI partition on the hard disk.
4. Finally, it loads the bootstrapper winload.efi (Windowssystem32winload.efi) based on the configuration content for system loading.

UEFI boot is a newer motherboard boot option seen as a successor to BIOS. Its main feature is the graphical interface, which facilitates user-friendly graphical operations.

Setting UEFI Boot Mode:

1. Connect a wired keyboard (recommended). Press the power button and then press Del to enter BIOS Setup. Use the arrow keys on the keyboard to navigate to Advanced > CSM Configuration > Set Boot Option Filter to [UEFI Only]. After configuring, press F10 to save and exit.

2. Press F10 to save the settings, and the PC will restart. Press F11 on the keyboard to enter the Boot Menu. (Note: If a hard disk or USB flash drive is installed or inserted but not recognized in the Boot Menu, it may not have the UEFI boot option.)

3. If you need to set the UEFI Boot Option as the default first boot option, select Enter Setup in the Boot Menu to enter BIOS Setup. Navigate to Boot > Boot Option #1 using the arrow keys (e.g., UEFI: USB Storage Device or Windows Boot Manager Hard Disk). Press F10 to save and exit.