How to configure the BIOS to boot from a flash drive

What is important to know about booting from a flash drive in the BIOS

When starting the computer, you can boot from different media, usually from the internal hard disk or SSD on which the operating system is installed. Less often, flash drives, external drives, and optical disks are used. You may also need to boot from a USB disk when installing OS on a new computer, reinstalling the system after a crash, searching for and removing viruses, starting from a backup disk, and in other similar cases.

In order for the PC to know which disk to boot from, there is a boot order (boot priority). This is one of the BIOS or UEFI options that allows you to set the priority of the boot media in the desired sequence. If the computer fails to boot from the first disk in the boot list, it tries the second, third, and so on.

You can use the Boot Menu to boot from a flash drive once, and the Boot Device Priority menu comes in handy to set permanent priorities. The latter differs slightly between text-based BIOS on older computers and UEFI, the successor to BIOS with a graphical shell and mouse support. Let's look at them separately.

How to configure the BIOS to boot from a USB flash drive via Boot Menu

For one-off cases, e.g. when checking for viruses, it is more convenient not to change the boot order, but to select the desired drive through the Boot Menu at startup. This is much faster and easier.

To get to this menu, plug in the flash drive, reboot the computer, and immediately after powering on, press the F12, F11, or Esc keys — the exact combination depends on the hardware manufacturer. Usually, the combination is indicated on the screen — you just have to spend additional seconds reading it. And in order not to miss the right moment, press the button several times until the menu opens.

The Boot menu looks like a simple table with a list of available boot disks, but it may look different. Using the arrows, select the USB Storage Device item (it can just be the name of the drive instead) and press Enter. This will start booting from the flash drive.

How to configure the BIOS to boot from a flash drive through the Boot Priority menu

With this option, you can set a constant boot priority that the PC will adhere to. To do this, plug in the drive, reboot the computer, and quickly press the Delete or F2 key repeatedly until the settings open. In rare cases, other keys may be used; see the separate BIOS login instructions for details.

Use the arrow keys on your keyboard to switch to the Boot tab, highlight the first item in the list and press Enter. Select the flash drive from the list and confirm with the Enter key. Press the F10 key to apply the assigned changes and press Enter again. The computer will restart and start booting from the USB flash drive.

The Boot menu is usually located on the main screen, but in some manufacturers' software, it may be hidden inside Advanced BIOS Features or Advanced Settings.

How to configure UEFI BIOS to boot from a USB flash drive through the Boot Priority menu

On modern computers, where UEFI is used instead of BIOS, the priority of the boot disks is set in a similar way. The differences are minimal and consist only of the interface.

Connect the flash drive to the PC and perform a reboot. Quickly press the Delete or F2 key as soon as the screen lights up after powering on.

Locate the Boot Device Priority or Boot Priority section. It is usually located on the Home screen. Try dragging the flash drive's name to the top of the list with your mouse — this works in many manufacturers' software. If you don't see such a section, switch to Advanced Mode or open the Advanced menu.

Here, in the expert menu, switch to the Boot tab, click on the first item in the list of bootable devices, and select your USB drive. Press the F10 key and confirm the changes to restart your computer and boot from the flash drive.