Ok, found the solution, just in case it ever comes up again. Upgrading the system BIOS to the most recent version (at this time A30) and then specifying no boot options allowed it to work fine.
When booting Knoppix 3.4 normally, X will only run in 640x480 resolution, no matter what is specified at boot time (i.e. screen=1024x768 doesn't do anything). Starting with fb1024x768 causes X to not be able to start at all. However, I have discovered that starting with the fb1024x768 option and (after X fails to start) then changing the driver in XF86Config-4 from "fbdev" back to "i810", X will then start in 1024x768. The only problem now (aside from that being kind of a hassle to do every boot) is that the colors seem a little off. I can't tell what depth it's actually running at now, but it looks like 256 colors.
Anyway, does anyone have any advice on what's going on here?
Ok, found the solution, just in case it ever comes up again. Upgrading the system BIOS to the most recent version (at this time A30) and then specifying no boot options allowed it to work fine.
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