I am a Knoppix dullard - up until today I had only ever used it to check disks.
I have a PC (Dell desktop) which refuses to boot, from HD, from Ubuntu installation CD, and from the Knoppix CD (6.2.1). It reads the CD or HD, but then freezes. This seems to happen when it tries to enter graphics mode. It also happily read a Windows installation CD up to the point where it wanted to install Windows.
The only way I can get it to boot with Knoppix is using the following cheat codes:
This scrolls a lot of messages, then returnsCode:knoppix vga=0 debug -b 3
The commands that are then available to me do not seem to include any that I can use to troubleshoot the hardware. I triedCode:Past mounting /mnt-system sh: can't access tty: job control turned off / #
but the pipe into less doesn't seem to work.Code:/ # dmesg | less
I Googled for help on using busybox, but can't find anything usefull.
Can anyone suggest how I can troubleshoot my PC from here, or other ways to boot Knoppix (I haven't tried all options yet)?
Another thing you might try is a different version of knoppix, especially for older hardware. I keep around old versions of knoppix for this very purpose. Try 5.1 if you can find it. How old is this desktop?

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