How to Change Boot Order in BIOS: A Complete Guide
Changing the boot order in BIOS is one of those tasks that sounds intimidating but follows a logical pattern once you understand what's actually happening. Whether you're installing a fresh operating system, recovering a system from a USB drive, or troubleshooting a PC that won't start correctly, adjusting the boot sequence is often the first step.
What Is Boot Order and Why Does It Matter?
When you power on a computer, the firmware — either BIOS (Basic Input/Output System) or its modern replacement UEFI (Unified Extensible Firmware Interface) — runs a startup routine that checks connected hardware. One of its key jobs is deciding which device to look at first when searching for an operating system to load.
That priority list is your boot order. Devices in the list typically include:
- Internal hard drives or SSDs
- USB flash drives or external drives
- Optical drives (DVD/Blu-ray)
- Network adapters (for PXE/network booting)
- SD card readers (on some systems)
If your internal drive is first in the list, your computer boots Windows, macOS, or Linux as normal. If you move a USB drive to the top, the system will attempt to boot from that device instead — which is exactly what you need when running a live OS environment or installing a new operating system.
How to Access BIOS or UEFI Settings 🖥️
Getting into BIOS/UEFI requires pressing a specific key immediately after powering on your computer — before the operating system begins loading. The window is short, often just a few seconds.
Common BIOS entry keys by manufacturer:
| Manufacturer | Common BIOS Key |
|---|---|
| Dell | F2 or F12 |
| HP | F10 or Esc |
| Lenovo | F1, F2, or Fn+F2 |
| ASUS | Del or F2 |
| Acer | F2 or Del |
| MSI | Del |
| Gigabyte | Del or F2 |
| Samsung | F2 |
Desktop motherboards often use Delete or F2. Laptops vary more widely by brand. If you miss the window, restart and try again — some systems show a prompt at the bottom of the screen indicating which key to press.
On Windows 10 and 11, you can also reach UEFI settings through software: go to Settings → System → Recovery → Advanced Startup → Restart Now, then navigate to Troubleshoot → Advanced Options → UEFI Firmware Settings.
Navigating the BIOS Interface
Once inside, the interface will be either an older legacy BIOS with a text-only menu navigated by keyboard, or a modern UEFI with a graphical interface that often supports mouse input.
In a legacy BIOS, look for a tab or section labeled:
- Boot
- Boot Sequence
- Boot Priority
- Boot Options
In a UEFI interface, you may find a simplified "Easy Mode" dashboard with a drag-and-drop boot priority section, or you'll need to switch to an "Advanced Mode" (often toggled with F7 or a button on screen).
Changing the Boot Order: Step by Step
In a legacy BIOS:
- Use arrow keys to navigate to the Boot tab
- Locate the Boot Priority Order or Boot Device Priority menu
- Use the keys shown on screen (commonly +/-, F5/F6, or Enter to select) to move your desired device to the top of the list
- Press F10 to save and exit — confirm when prompted
In a UEFI interface:
- Enter Advanced Mode if necessary
- Navigate to the Boot section
- Select Boot Option #1 and choose your target device from the dropdown, or drag and drop devices in Easy Mode
- Save settings and exit — usually F10 or an on-screen Save & Exit button
The computer will restart and attempt to boot from the device now listed first.
Key Variables That Affect Your Experience
Not every system behaves the same way, and a few factors will shape how straightforward this process is for you.
UEFI Secure Boot is one of the most common complications. Many modern systems have Secure Boot enabled by default, which prevents booting from unsigned or unrecognized media. If your USB drive isn't loading even after changing boot order, Secure Boot may be blocking it. This setting is typically found under the Security or Boot tab in UEFI and can be disabled — though doing so has security implications worth understanding before you proceed.
Fast Boot or Fast Startup is another factor. When enabled, the system skips parts of the hardware check cycle to start faster, sometimes bypassing the BIOS key window entirely. Disabling Fast Boot in BIOS and Fast Startup in Windows can make the firmware more consistently accessible.
Drive formatting matters too. A USB drive formatted as MBR may not be recognized by a UEFI-only system expecting GPT-formatted media, and vice versa. The partitioning scheme of your bootable media needs to match your firmware mode — UEFI or Legacy/CSM.
Legacy/CSM Mode (Compatibility Support Module) is a UEFI feature that emulates older BIOS behavior. Some bootable drives only work with CSM enabled; others work better with it disabled. The right setting depends entirely on what you're booting from and how it was prepared. 🔧
When Boot Order Changes Don't Stick
Some systems reset boot order on every restart, especially if a one-time boot option was used. Most BIOS/UEFI environments offer a "Boot Override" or "One-Time Boot" option — often accessible at startup via a key like F12, F11, or Esc — which lets you choose a boot device for a single session without permanently changing your stored settings. This is useful for running a recovery tool once without altering your normal setup.
If changes aren't persisting, it may also indicate a depleted CMOS battery on older motherboards, which can cause BIOS settings to revert to defaults after power loss.
The Setup That Determines What Works for You
The steps above work consistently across most systems — but the specific keys, menu labels, Secure Boot status, drive formatting, and CSM settings on your machine are what determine whether the process goes smoothly or requires a few extra troubleshooting steps. A gaming desktop with a custom ASUS motherboard, a corporate Dell laptop with managed BIOS settings, and a budget Acer notebook will each present a slightly different version of this process. Your firmware version, what you're booting from, and how that media was created all feed into the same outcome in different ways.