I know this has been covered in other posts, but I think it _may_ help others. I finally got Ubuntu to install on my Ultra60. Basically, when I tried to install from the first CD I burned, I got the Illegal Instruction error. So it was off to net boot, However, I was getting Timeout for ARP/RARP request every time I tried. So i read somewhere that perhaps the speed I wrote the CD with may be part of the problem. Sure enough I wrote the CD at 8x and bammmm it worked. Hope this might help others.
Mike