Running Linux, 5th Edition - Matthias Kalle Dalheimer [324]
If you have a modern serial mouse, you could also try specifying Auto, which will try to autoselect a mouse driver.
It is easy to check whether you have selected the correct mouse driver once you have started up X: when you move your mouse, the mouse pointer on the screen should follow this movement. If it does this, your setup is very likely to be correct. If it doesn't, try another driver, and also check whether the device you specified is correct.
The next section of the xorg.conf file is Device, which specifies parameters for your video card. If you have multiple video cards, there will also be multiple Device sections.
Section "Device"
BoardName "Radeon LW"
BusID "1:0:0"
Driver "radeon"
Identifier "Device[0]"
Screen 0
Option "Rotate" "off"
VendorName "ATI"
EndSection
The first entry here, BoardName, is simply a descriptive name that reminds you which graphics card you have configured here (important if you have more than one!). Similarly, VendorName is a free-form string that has purely descriptional purposes. Even the Identifier string can be picked freely, but needs to match the Device strings used in later sections of the configuration file. It is customary here to use the names Device[0], Device[1], and so on.
BusID identifies the actual graphics card in terms of the built-in hardware on the PCI bus. PCI:1:0:0, or the shorter 1:0:0, is usually the right choice if you have only one choice. If you are unsure about what to put in here, run the X server as follows:
X.org -scanpci
and check the output carefully. At least one graphics card should be contained in the output (probably among other hardware not relevant here). For example, a line like:
(1:0:0) Matrox unknown card (0x19d8) using a Matrox MGA G400 AGP
tells you that you have a Matrox MGA G400 card with an AGP connector installed. The first digits in parentheses are the PCI bus ID, as described earlier.
The Screen section is mandatory on multihead graphics cards, which have more than one monitor output. For single-head graphics cards, always put in 0 here.
Driver is very important, because it determines the actual graphics driver to be loaded by the X server. A good way to find the right driver name is either to use the configuration programs described earlier or to run the X server like this:
Xorg -probeonly
This will output information the X server has collected about your hardware, including the driver it thinks it should use.
There are lots of other options you can specify in this file, including the chipset, the RAMDAC, and other hardware properties, but the X server is very good at finding these out all by itself, so you usually don't have to do that. If you still want to, check out the driver-specific README file, which lists the options and their possible values for that driver.
The next section is Monitor, which specifies the characteristics of your monitor. As with other sections in the xorg.conf file, there may be more than one Monitor section. This is useful if you have multiple monitors connected to a system, or if you use the same xorg.conf file under multiple hardware configurations. In general, though, you will need only a single Monitor section:
Section "Monitor"
Option "CalcAlgorithm" "CheckDesktopGeometry"
DisplaySize 320 240
HorizSync 28-60
Identifier "Monitor[0]"
ModelName "THINKPAD 1400X1050 LCD PANEL"
Option "DPMS"
VendorName "IBM"
VertRefresh 50-60
UseModes "Modes[0]"
EndSection
The Identifier line is used to give an arbitrary name to the Monitor entry. This can be any string; you will use it to refer to the Monitor entry later in the xorg.conf file.
HorizSync specifies the valid horizontal synchronization frequencies for your monitor in kHz. If you have a multisync monitor, this can be a range of values (or several comma-separated ranges), as seen