Sounds like possibly a video problem?

Have you tried any of the knoppix boot options (cheat codes, press <F2> at the startup screen to see some of them)

knoppix vga=normal
---for a standard vga mode instead of the 130x50 text mode...

knoppix 2 vga=normal
---for text-only console mode

knoppix expert
--- for no auto config

etc., just a thought, at least then you would have an idea if your cd is OK.

I have run into one machine that I can't get knoppix to run on from CD, it's a gateway, it'll run fine with a pre-installed linux hard drive but won't boot from the knoppix cd or into the cd from a floppy. I've also read of some newer athlon (I think) mobos that won't run knoppix.

HTH

rock