LinuxQuestions.org - xserver in 8 bit mode??

The /etc/X11/XF86Config-4 file is the one you want to modify. Towards the bottom, there ought to be a section that looks like this:

Code:

Section "Screen"

Identifier "screen1"

Device "device1"

Monitor "monitor1"

DefaultColorDepth 24

The DefaultColorDepth line specifies which color depth X will start in. Below that, there will be several portions like this:

Code:

Subsection "Display"

Depth 8

Modes "800x600" ...

EndSubSection

Those define the color depths and resolutions you'll have available at those depths. Unless you know what you're doing, don't mess with these too much; the resolution supported at a specific depth depends on your graphics card and monitor, so the values that are already there should be appropriate for your hardware.