i've got exactly the same problem on a Compaq Deskpro EN 6400/6.4.
It must be a Compaq BIOS problem?
I have already noticed this qeury on linuxquestions.org, but there was not an answer to this.
I try booting Knoppix from CD on my Compaq Armada 7400 laptop, but not successful, the CD is found, SYSLINUX is started, but then boot process halts (I can see the message SYSLINUX DEBIAN 2.04 (Debian, 2003-06-06) followed by a bunch of garbage symbols). When I boot Knoppix from diskette using the same CD, the system loads without any problem. Another hint is that I can boot the system from the same CD on another laptop Compaq Evo N600c.
Appreciate every advice.
i've got exactly the same problem on a Compaq Deskpro EN 6400/6.4.
It must be a Compaq BIOS problem?

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