On most PPC system we use the XF68_FBDev. Unlike previous X servers this one requires more setup. First you will need to run the Xconfigurator program (this is done in the installer.) The Xconfigurator should get X up and running, however you may wish to further customize it. One way is to use the fbset program.
First put your monitor into the resolution you want:
fbset -xres 1024 -yres 768 -depth 32
Next to get a custom modeline for X:
fbset -x
You will get output such as:
Mode "name"
# D: 106.735 MHz, H: 75.378 kHz, V: 93.289 Hz
DotClock 106.736
HTimings 1024 1056 1192 1416
VTimings 768 772 776 808
Flags "-HSync" "-VSync"
EndMode
That information should be copied into the /etc/X11/XF86Config file. It should be placed under the comment about the Apple Power G3.
Next scroll down further until you see something similar to:
Section "Screen"
Driver "fbdev"
Device "control"
Monitor "Apple Multiple Scan 15 Display"
Subsection "Display"
Depth 8
Modes "832x624"
ViewPort 0 0
Virtual 832 624
EndSubsection
EndSection
Change the "832x768" line to "name" and the Virtual 832 624 to Virtual 1024 768. Save your changes and run X.