I have an Ubuntu setup on a USB, but the problem is I can't choose to boot from USB in BIOS. I can only choose my hard drive, DVD drive and flopy. I have motherboard ASUS P5LD2
migrated from serverfault.com Oct 24 '11 at 18:14
To boot from a USB Drive you need to connect the boot drive, then boot the computer to the BIOS.
Once in the BIOS, go to the "Boot" Tab and select the "Removeable Drives" option, make sure the "1st Drive" is set to the [USB DRIVE]. Then in the "Boot Device Priority" select the [USB DRIVE] as the "1st Boot Device", from there save settings and exit, the computer should boot from the USB assuming the USB drive is bootable.