After trying to install Debian Linux from CD I now can only get half of the display to show up.
I can only view the lower half of the screen in GUI mode. I have ruled out the monitor as the culprit. It is fine on other workstations, displays full screen when at a commandline. Other monitors act exactly the same when trying to use them instead. I can boot the computer to "another OS" and it is fine. Telling me the onboard card is OK as well.

It is an older IBM desktop sporting a P100 processor , 32 megs mem, onboard video (supported, S3 Trio64) with 1 meg of built in video memory. SuperProbe reports everthing correctly.
The contents of /etc/X11/XF86config-4 looks right. I dont see anything out of place with it. but could post relative portions for checking.
Running xf86config and re-iputing all the correct parameters hasnt helped. Afterwards, I shutdown X with (ctrl+alt+BkSp) and restart it again but to no avail. Still the same. Everything above the middle of the "X" in the center of the screen is gone. And toggling resolution makes no change it stays at half screen 640X480.

A second problem is that the mouse is completely unresponsive. I have tried a couple of different mice and even a serial mouse but still no-go. But the display is first priority.

What is there that I might have overlooked ? Any help correcting this is certainly appreciated.

I'd like an answer to this too, as I am in the same situation only my mouse works! IBM monitor, old 486, Slackware 8.0, Avance Logic 2101 video card.

If you could post your configuration file (/etc/X11/XF86Config), it would
be a lot easier to help diagnose the problem.
When you say "everything above . . . is gone", do you mean it's truncated, or
it's squished down to a couple pixels?
Can you get it to work with the basic SVGA driver?

Thanks for such a quick reply Moses.
Its a long file...as you know .. and its on another computer and I'm running windows on the one I'm posting this with- are there parts which are more relevant that I can get for you? Like here's the screen section:


Section "Screen"
Identifier "Screen1"
Device "Avance Logic 2101"
Monitor "My Monitor"
DefaultDepth 8

Subsection "Display"
Depth 8
Modes "640x480" "800x600" "1024x768"
ViewPort 0 0
EndSubsection

Subsection "Display"
Depth 16
Modes "640x480" "800x600"
ViewPort 0 0
EndSubsection

Subsection "Display"
Depth 24
Modes "640x480"
ViewPort 0 0
EndSubsection
EndSection

Also post the graphics device section.

When you say "everything above . . . is gone", do you mean it's
truncated, or it's squished down to a couple pixels?

The problem was that xf86config was recognising the card as a vga card instead of as a vesa card. The correct driver made a tremendous difference. I guess the resolution wasnt half of 640x480 but 320x200. I did get 800x600x8bpp and 800x600x16bpp to work without trouble. The monitor has trouble trying to sync much more than that.