
           Log of BUGS and programs with the Universal VESA VBE
           ----------------------------------------------------

This file documents known problems with the Universal VESA VBE. I have done
my best to try to fix all know problems, but some still persist and may
well be limitations in the particular video controller hardware and
may not be fixable.

Cirrus CL-GD542x chipsets:

    - The Cirrus 5422 chipsets will not allow extended CRT addressing to
      work correctly in 640x480x16 and 320x200x256. This problem is
      not specific to the Universal VESA VBE but also turns up in the
      VBE compliant BIOS on most cards. It may be a hardware problem
      (and may be fixed in newer chipsets)

Trident 8900/9000 chipsets:

    - The Trident 8900 chipsets will not allow the extended CRT addressing
      to pass the 512k memory mark, so page flipping will not work correctly
      on 1Mb cards that try to access the upper 512k. There may be a
      register value which will enable this, but I have not been able to
      fix the problem.

S3 86c911:

    - The S3 86c911 has some severe bugs in the extended CRT addressing
      code in 1024x768 16 color modes. Page flipping works but looks
      disgusting (bottom 1/8th of the screen is trashed). This bug is
      fixed in the 924 and later chipsets.

Video7 chipsets:

    - The video7 chipsets do not work presently. I am getting a Video7
      board to test so should be able to fix the problems for a later
      release.

QEMM memory manager:

    - QEMM does some wierd things with the video BIOS, so you may encounter
      problems when using the Universal VESA VBE with QEMM installed.
      You will need to use the exclude option to get it to work at all
      (see the readme file).

