I use the last 686 ubuntu kernel image (I have a celeron): Linux antre 2.6.15-26-686 #1 SMP PREEMPT Thu Aug 3 03:13:28 UTC 2006 i686 GNU/Linux But I got the same problem with the 386 image Linux antre 2.6.15-26-386 #1 PREEMPT Thu Aug 3 02:52:00 UTC 2006 i686 GNU/Linux -- No boot with USB DVD drive https://launchpad.net/bugs/59099