Datasheet

“main” (Installation and Administration) — 2004/6/25 — 13:29 — page 283 — #309
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12
The X Window System
Use the DefaultDepth setting to select the color depth the server should
use unless it is started with a specific color depth. There is a Display sub-
section for each color depth. The keyword Depth assigns the color depth
valid for this subsection. Possible values for Depth are 8, 15, 16, and 24.
Not all X server modules support all these values.
After the color depth, a list of resolutions is set in the Modes section. This
list is checked by the X server from left to right. For each resolution, a suit-
able Modeline is searched in the Modes section. The Modeline depends
on the capability of both the monitor and the graphics card. The Monitor
settings determine the resulting Modeline.
The first resolution found is the Default mode. With
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+ (on the
number pad), switch to the next resolution in the list to the right. With
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– (on the number pad), switch to the left. This enables you to
vary the resolution while X is running.
The last line of the Display subsection with Depth 16 refers to the size of
the virtual screen. The maximum possible size of a virtual screen depends
on the amount of memory installed on the graphics card and the desired
color depth, not on the maximum resolution of the monitor. Because mod-
ern graphics cards have a large amount of video memory, you can create
very large virtual desktops. However, you may no longer be able to use 3D
functionality if you fill most of the video memory with a virtual desktop. If
the card has 16 MB video RAM, for example, the virtual screen can be up
to 4096x4096 pixels in size at 8-bit color depth. Especially for accelerated
cards, however, it is not recommended to use all your memory for the vir-
tual screen, because this memory on the card is also used for several font
and graphics caches.
12.1.2 Device Section
A device section describes a specific graphics card. You can have as many
device entries in XF86Config as you like, as long as their names are dif-
ferentiated, using the keyword Identifier. As a rule — if you have more
than one graphics card installed — the sections are simply numbered in or-
der. The first one is called Device[0], the second one Device[1], and so
on. The following file shows an excerpt from the Device section of a com-
puter with a Matrox Millennium PCI graphics card:
Section "Device"
BoardName "MGA2064W"
BusID "0:19:0"
283SUSE LINUX Enterprise Server