Creation of Functional, Minimal, and Correct Xorg.conf [SOLVED]

Question

Being fairly new to GNU/Linux in general, and totally green in doing things myself, I foolishly avoided the building of an xorg.conf. Following the beginner's guide in the wiki, I just did an "xorg --configure" which created a base xorg.conf for me. It worked, and I noticed no problems in the general use of my window manager (xmonad). I have an ATI Mobility Radeon X1300.
I discovered today that I was using the radeonhd driver which was giving me terrible performance in OpenGL applications, so edited xorg.conf to revert back to the plain radeon driver. Upon restarting X, my performance problems were gone, but my fonts in the Firefox interface devolved... I have taken this a wakeup call to actually write a good xorg.conf and to understand what everything in it is for.
I have done plenty of configuration, though I have never before looked into editing the dreaded xorg.conf, coming from Ubuntu, so I know very little. Any help would be greatly appreciated.
Specifics:
What parts are necessary?
How do I get the fonts I had before back?
Graphics is all that concerns me, I have no strange input devices, and my touchpad works fine (I configured the fdi files for that).
I will list my current xorg.conf below. Fonts worked before I changed the driver from radeonhd to radeon and enabled the option for EXA. Before these changes, all the text contained therein was created automagically by xorg. I have a feeling most of this is unnecessary.
Section "ServerLayout"
Identifier "X.org Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
ModulePath "/usr/lib/xorg/modules"
FontPath "/usr/share/fonts/misc"
FontPath "/usr/share/fonts/100dpi:unscaled"
FontPath "/usr/share/fonts/75dpi:unscaled"
FontPath "/usr/share/fonts/TTF"
FontPath "/usr/share/fonts/Type1"
EndSection
Section "Module"
Load "glx"
Load "extmod"
Load "record"
Load "dri"
Load "dbe"
Load "dri2"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5 6 7"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
EndSection
Section "Device"
### Available Driver options are:-
### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
### [arg]: arg optional
#Option "NoAccel" # [<bool>]
#Option "AccelMethod" # [<str>]
#Option "offscreensize" # [<str>]
#Option "SWcursor" # [<bool>]
#Option "ignoreconnector" # [<str>]
#Option "forcereduced" # [<bool>]
#Option "forcedpi" # <i>
#Option "useconfiguredmonitor" # [<bool>]
#Option "HPD" # <str>
#Option "NoRandr" # [<bool>]
#Option "RROutputOrder" # [<str>]
#Option "DRI" # [<bool>]
#Option "TVMode" # [<str>]
#Option "ScaleType" # [<str>]
#Option "UseAtomBIOS" # [<bool>]
#Option "AtomBIOS" # [<str>]
#Option "UnverifiedFeatures" # [<bool>]
#Option "Audio" # [<bool>]
#Option "HDMI" # [<str>]
#Option "COHERENT" # [<str>]
Identifier "Card0"
Driver "radeon"
VendorName "ATI Technologies Inc"
BoardName "M52 [Mobility Radeon X1300]"
BusID "PCI:1:0:0"
Option "AccelMethod" "EXA"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
SubSection "Display"
Viewport 0 0
Depth 1
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 4
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 8
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 15
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 16
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
EndSubSection
EndSection
Last edited by egan (2009-09-27 17:28:50)

Answer 1

skottish wrote:
X searches all of the directories that you had in your original xorg.conf file, and it will load whatever it needs automatically. I don't think your problem is specifically with xorg.conf (or lack of), I think what you're seeing is the DPI changing between drivers.
Try this with each driver loaded and see if they're different:
xdpyinfo | grep resolution
Ah, yes indeed!
radeonhd: 96x96
radeon: 129x127
How do I get X with the radeon driver to use 96x96?
EDIT: Adding a dpi argument of 96 to /etc/X11/xinit/xserverrc fixed the problem. I didn't occur to me that the two drivers would use different dpis.
Thank you so much!
Last edited by egan (2009-09-27 17:13:28)