Boot USB drive on older BIOS

Last Modified: Mon, 01 Mar 2010 20:29:46 +0000 ; Created: Fri, 26 Feb 2010 16:22:39 +0000

Some older BIOS have early USB boot support, but it doesn't alway seem to work.

I have a EliteGroup K7S5A Pro motherboard that detects a 1GB USB flash drive as "USB-RFD" that will not boot from a normally formatted and partitioned USB drive. I found the following solutions to handle older BIOS with legacy USB boot methods.

BIOS settings to use:

  1. USB Function Support = Enabled
  2. USB Function for DOS = Disabled
  3. Thumb = Disabled
  4. Hit F8 to bring up the boot menu or configure it in your bios if you like

Making the USB drive bootable:

  1. Plug the USB drive into a Linux machine
  2. Wipe the drive with dd if=/dev/zero of=/dev/sdX bs=64k
  3. mkdiskimage -4 /dev/sdX 0 64 32
    • This creates a single partition as the "4th" partition which allows the older BIOS to boot the usb drive like a ZIP drive which it expects since it uses an older boot method
    • You can also use another partition program and mkfs just make sure to create it as the 4th partition with 64 heads, 32 sectors
  4. mkfs.msdos /dev/sdX4 (Important that it is made FAT16)
  5. syslinux /dev/sdX4 to make it bootable