Quote Originally Posted by deesy58
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When I originally set up my Knoppix persistent image, I had the resolution set to 1024x768, but it seems to make no difference what values I specify at boot time - I still can't get the monitor to work.
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Deesy
Have you tried NOT loading the image (hit cancel or escape)?
The image has Xorg.conf file (IIRC) that may override the screen=

If this helps, you may have to mount the image and delete some settings files.
I think also that K511 persistent images often got corrupted due to some kernel bug.
If yours is good, keep a backup.