You need the computer to start from a USB installer, a rescue drive, or a different internal disk instead of the usual Windows drive. These steps apply to Dell, HP, Lenovo, Asus, Acer, and custom desktop systems, though exact menu names vary.
You are changing firmware settings that control startup. Change only boot order or one-time boot selection unless you understand the other options. Disk mode, Secure Boot, virtualization, and storage-controller changes can stop Windows from booting if changed incorrectly. We provide no warranty; proceed at your own risk.
Does This Affect You?
Boot order is the list of devices the PC checks during startup. Normally the Windows SSD or hard drive sits first. You change it when you want to boot from a USB installer, run recovery media, start a diagnostic tool, or choose a different internal drive.
Enter the BIOS/UEFI Setup Screen
The tricky part is usually timing the key press right after power-on.
- Restart the PC or turn it on from a full shutdown.
- As soon as the logo appears, repeatedly tap the BIOS key. Common keys are F2 or Delete for many motherboards and Dell systems, F10 for HP, F2 or the Novo button for Lenovo, and F2 or Delete for Asus and Acer.
- If Windows loads, restart and try again. Missing the window does not hurt anything.
- If fast boot makes the window too short, open Windows Settings > System > Recovery, choose Restart now beside Advanced startup, then go to Troubleshoot > Advanced options > UEFI Firmware Settings > Restart.
Change the Boot Order
Once inside BIOS or UEFI, the layout changes by brand but the logic is the same.
- Open the Boot, Boot Order, or Boot Priority section. Use arrow keys if the firmware does not support the mouse.
- Find the list of bootable devices, such as the Windows drive, USB drive, optical drive, and network boot option.
- For a one-time USB boot, use the Boot Menu or One-Time Boot option if available. It is often accessed at startup with F12 or Esc.
- For a permanent order change, select the device and move it to the top using the keys shown on-screen, commonly +/–, function keys, or drag-and-drop in newer UEFI screens.
- Press the save key, often F10, choose Save and Exit, and confirm.
- After you finish installing Windows or using the recovery tool, move the normal Windows drive back to the top so startup returns to normal.
Plug the USB drive in before entering BIOS because many systems scan boot devices only during startup. Also make sure the USB was created as bootable with a tool such as Rufus or the Windows Media Creation Tool; copying files to a blank USB stick usually is not enough.
Secure Boot can block some Linux installers and older rescue tools. If a known-good USB still will not boot, temporarily disabling Secure Boot may help, but turn it back on afterward unless you have a specific reason not to. Older USB media may also need Legacy or CSM mode to appear in the boot list. If boot order changes never save reliably, use the one-time boot menu for USB installs and repairs.
Sources
- Microsoft Support – Change the boot order on Windows devices (2025)
- Dell – Changing the Boot Sequence in BIOS (2025)
- ASUS Support – How to Enter BIOS and Change Boot Priority (2024)