x86emu fails when fetching monitor data (INVPLG instruction?)

[Nolan Check]

I own a Toshiba Tecra 8000 laptop. The display device is a NeoMagic
MagicGraph256AV, which uses the NM2200 chipset. The monitor goes up to
1024x768. When I install Xubuntu Gutsy Tribe 5 (with latest updates), it
fails to detect the screen resolutions properly. It maxes out at 640x480
until I adjust the HorizSync and VertSync parameters in /etc/X11/xorg.conf.
The reason for this seems to be that X.Org fails to call the video BIOS
function to get monitor data. (See attached /var/log/Xorg.0.log)

During the VBE DDC transfer, it gets "01 ILLEGAL X86 EXTENDED OPCODE". That
indicates the opcode "0F 01", correct? The INVPLG instruction.

Does it sound plausible that the INVPLG instruction is used in my video
BIOS?
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