Linux Articles listed under "USB Boot CD Ubuntu 9.10"
How to create a USB Boot CD that can be used to boot your Ubuntu Live USB Flash Drive from a computer with a BIOS that doesn't support booting from USB. The USB Boot CD you create via this tutorial will contain the USB drivers necessary to open a USB connection. GRUB is used to launch initrd (Initial Ram Filesystem) from the CD. The Initial Ram Filesystem then locates the squash filesystem and persistent casper-rw persistence block file on the USB device and proceeds to boot the Live USB Persistent environment.