The following list of USB BIOS boot settings and options has been thoroughly tested with various Linux USB installs. While there may be additional options, this guide serves as a simple checklist to help familiarize you with boot options and their usage. Be sure to check back often, as I will continuously update this list with new information.
Newer UEFI or BIOS USB Boot Settings
Most modern computers are designed to automatically detect USB devices as hard drives, simplifying the boot process. If your system supports this feature, follow these steps to Access BIOS USB Boot Menu, also known as the Boot Manager:
Steps to Access the Boot Menu
- Restart your computer.
- Press the appropriate BIOS Hotkey (F2, F10, F11, or ESC) during the POST (Power-On Self-Test).
- Select your USB DISK from the Boot Menu.
- Resume startup.
Older USB BIOS Boot Settings (USB-HDD)
For older systems or those using simplified BIOS interfaces, you might not have access to a Boot Menu. In these cases, you will need to manually configure the BIOS to detect and boot your USB device.
Preferred USB Boot Method
- USB-HDD: This option is recommended for systems that support it, as it typically allows you to boot Linux from larger USB flash drives. A BIOS that recognizes USB-HDD automatically detects the drive’s geometry.
Alternative USB Boot Methods
- USB-ZIP: While this method may work, it often requires you to modify the drive geometry to match how the BIOS recognizes the device.
- USB-FDD: This option is generally unsupported and not recommended.
In summary, if your system BIOS supports the USB-HDD boot option, it should effectively boot Linux from a large capacity bootable USB flash drive. For older systems that do not support USB-HDD, the USB-ZIP option can be used, although it may require geometry modifications. This usbkey.txt Syslinux documentation provides excellent methods for modifying flash drive geometry.
Exception for USB-ZIP Booting: The USB-ZIP boot option may allow you to boot some larger capacity flash drives without geometry modifications if your flash drive appears as a selectable hard drive under boot priority. This is common on systems using an Award-Phoenix BIOS.
Steps to Configure Older BIOS:
- Enter BIOS Setup:
- Restart your computer.
- Press the appropriate key (Del, F2, F10, Esc, or F12) to enter BIOS setup.
- Change Boot Order:
- Locate the boot order settings (usually found under "Boot," "Advanced BIOS Features," or similar).
- Set USB-HDD as the first boot device.
- Save and Exit:
- Save changes and exit BIOS setup (usually by pressing F10 and confirming).
Other BIOS USB Booting Tips
- First Boot Device: If your BIOS lists the USB memory stick as a hard drive, select it as the first boot device.
- Remove Conflicting Boot Options: Eliminate other USB boot options from the boot priority list when attempting to boot from USB-ZIP or USB-HDD to avoid conflicting startup cues.
- Filesystem and Active Partition: The filesystem used may also affect the BIOS's ability to detect and boot the drive. If a FAT filesystem doesn't work, try FAT32. The partition must also be active, or the device will not boot.
- BIOS Updates: Keep an eye out for BIOS updates from your motherboard manufacturer. There may be bug fixes related to USB boot issues.
- Recent BIOS Support: Based on experience, most "recent" Award/Phoenix and AMI BIOS systems generally support USB booting.
USB Booting Troubleshooting
- USB Drive Not Recognized: Ensure the USB drive is properly formatted and contains a bootable image. Software tools like UUI can help you effortlessly create bootable USB drives.
- BIOS Not Showing USB Option: Try different USB ports and ensure the USB drive is plugged in before powering on the system.
- Legacy Boot and Secure Boot: If you're having trouble, you may need to enable Legacy Boot and disable Secure Boot in BIOS settings.
- Revert Changes: If necessary, revert BIOS boot settings to default by selecting the appropriate option in BIOS setup.
By following these guidelines, you can effectively configure your system to boot from a USB drive, allowing for a wide range of applications from OS installations to system recovery. If you still need more help, feel free to check out our USB BIOS Booting Tips section.