Si ca peut t'aider, voici ma conf XFree (sous OpenBSD) :
Section "ServerLayout"
Identifier "XFree86 Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
RgbPath "/usr/X11R6/lib/X11/rgb"
ModulePath "/usr/X11R6/lib/modules"
FontPath "/usr/X11R6/lib/X11/fonts/100dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/75dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/CID/"
FontPath "/usr/X11R6/lib/X11/fonts/Speedo/"
FontPath "/usr/X11R6/lib/X11/fonts/TTF/"
FontPath "/usr/X11R6/lib/X11/fonts/Type1/"
FontPath "/usr/X11R6/lib/X11/fonts/cyrillic/"
FontPath "/usr/X11R6/lib/X11/fonts/encodings/"
FontPath "/usr/X11R6/lib/X11/fonts/local/"
FontPath "/usr/X11R6/lib/X11/fonts/misc/"
EndSection
Section "Module"
Load "dbe"
Load "extmod"
Load "glx"
Load "record"
Load "xtrap"
Load "speedo"
Load "type1"
Load "freetype"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "keyboard"
Option "XkbRules" "xfree86"
Option "XkbModel" "logicordless"
Option "XkbLayout" "fr"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "wsmouse"
Option "Device" "/dev/wsmouse0"
Option "ZAxisMapping" "4 5"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
HorizSync 31.5 - 182.0
VertRefresh 40.0 - 250.0
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 "SWcursor" # [<bool>]
#Option "UsePIO" # [<bool>]
#Option "ShowCache" # [<bool>]
#Option "VideoKey" # <i>
#Option "NoSLI" # [<bool>]
#Option "TexturedVideo" # [<bool>]
#Option "DRI" # [<bool>]
Identifier "Card0"
Driver "tdfx"
VendorName "3dfx Interactive"
BoardName "Banshee"
ChipSet "3dfx Banshee"
BusID "PCI:1:0:0"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
DefaultDepth 16
SubSection "Display"
Depth 1
EndSubSection
SubSection "Display"
Depth 4
EndSubSection
SubSection "Display"
Depth 8
EndSubSection
SubSection "Display"
Depth 15
EndSubSection
SubSection "Display"
Depth 16
Modes "1280x1024" "1024x768" "800x600" "640x480" "720x576"
EndSubSection
SubSection "Display"
Depth 24
Modes "1280x1024" "1024x768" "800x600" "640x480" "720x576"
EndSubSection
EndSection
Section "DRI"
Group "video"
Mode 0666
EndSection
-=[j@synchron]=(~)> cat /etc/X11/XF86Config <(23:14:18)
Section "ServerLayout"
Identifier "XFree86 Configured"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
RgbPath "/usr/X11R6/lib/X11/rgb"
ModulePath "/usr/X11R6/lib/modules"
FontPath "/usr/X11R6/lib/X11/fonts/100dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/75dpi/"
FontPath "/usr/X11R6/lib/X11/fonts/CID/"
FontPath "/usr/X11R6/lib/X11/fonts/Speedo/"
FontPath "/usr/X11R6/lib/X11/fonts/TTF/"
FontPath "/usr/X11R6/lib/X11/fonts/Type1/"
FontPath "/usr/X11R6/lib/X11/fonts/cyrillic/"
FontPath "/usr/X11R6/lib/X11/fonts/encodings/"
FontPath "/usr/X11R6/lib/X11/fonts/local/"
FontPath "/usr/X11R6/lib/X11/fonts/misc/"
EndSection
Section "Module"
Load "dbe"
Load "extmod"
Load "glx"
Load "record"
Load "xtrap"
Load "speedo"
Load "type1"
Load "freetype"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "keyboard"
Option "XkbRules" "xfree86"
Option "XkbModel" "logicordless"
Option "XkbLayout" "fr"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "wsmouse"
Option "Device" "/dev/wsmouse0"
Option "ZAxisMapping" "4 5"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
HorizSync 31.5 - 182.0
VertRefresh 40.0 - 250.0
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 "SWcursor" # [<bool>]
#Option "UsePIO" # [<bool>]
#Option "ShowCache" # [<bool>]
#Option "VideoKey" # <i>
#Option "NoSLI" # [<bool>]
#Option "TexturedVideo" # [<bool>]
#Option "DRI" # [<bool>]
Identifier "Card0"
Driver "tdfx"
VendorName "3dfx Interactive"
BoardName "Banshee"
ChipSet "3dfx Banshee"
BusID "PCI:1:0:0"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
DefaultDepth 16
SubSection "Display"
Depth 1
EndSubSection
SubSection "Display"
Depth 4
EndSubSection
SubSection "Display"
Depth 8
EndSubSection
SubSection "Display"
Depth 15
EndSubSection
SubSection "Display"
Depth 16
Modes "1280x1024" "1024x768" "800x600" "640x480" "720x576"
EndSubSection
SubSection "Display"
Depth 24
Modes "1280x1024" "1024x768" "800x600" "640x480" "720x576"
EndSubSection
EndSection
Section "DRI"
Group "video"
Mode 0666
EndSection