Section "Module"
Load "dbe" # Double buffer extension
SubSection "extmod"
Option "omit xfree86-dga" # don't initialise the DGA extension
EndSubSection
# Load "type1"
Load "freetype"
# Load "xtt"
Load "glx"
Load "dri"

EndSection

Section "Files"
FontPath "/usr/share/fonts/misc"
FontPath "/usr/share/fonts/100dpi:unscaled"
FontPath "/usr/share/fonts/75dpi:unscaled"
FontPath "/usr/share/fonts/Type1"
EndSection

Section "InputDevice"
Identifier "Keyboard1"
Driver "kbd"
Option "AutoRepeat" "500 30"
Option "XkbRules" "xorg"
Option "XkbModel" "pc101"
Option "XkbLayout" "us"
EndSection

Section "InputDevice"
Identifier "Mouse1"
Driver "mouse"
Option "Protocol" "Auto" # Auto detect
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5 6 7"
EndSection

Section "Monitor"
Identifier "acer"
HorizSync 31.5 - 64.3
VertRefresh 60
EndSection

Section "Device"
Identifier "ati x1950 pro"
Driver "fglrx"
BusID "PCI:6:0:0"
#VideoRam 524288
# Insert Clocks lines here if appropriate
EndSection

Section "Screen"
Identifier "Screen 1"
Device "ati x1950 pro"
Monitor "acer"
DefaultDepth 24

Subsection "Display"
Depth 24
Modes "1920x1200" "1600x1200" "1280x1024" "800x600" "640x480"
ViewPort 0 0
EndSubsection
EndSection

Section "ServerLayout"
Identifier "Simple Layout"
Screen "Screen 1"
InputDevice "Mouse1" "CorePointer"
InputDevice "Keyboard1" "CoreKeyboard"
EndSection

Section "DRI"
Mode 0666
EndSection
--------------------------
I installed ati-driver-installer-8-9-x86.x86_64 and ran 'aticonfig --initial' but that config didnt work so I made this one. This is totally new as now I am running Archlinux_x64. This config works fine when I change driver from 'fglrx' to 'vesa'.
I don't get why 'fglrx' and 'dri' modules are not being found when I try this configuration out.
lsmod verifies fglrx is loaded.

The Arch wiki for ati cards has installation tips and a trouble shooting section.

it was apparently not findin the libs since there is only one 'ModulePath' section for the xorg.conf it wasnt able to see the x86 and x86_64 lib paths at once. I ended up making softlinks to the other end.

#!/bin/bash
#AFTER USER STARTED Xorg
uzer=`ls /home/`
pth="/usr/lib/xorg/modules"
pth64="/usr/lib64/xorg/modules"
cd $pth64
ln -s $pth/libpcidata.so libpcidata.so
ln -s $pth/libfb.so libfb.so
ln -s $pth/libxaa.so libxaa.so
ln -s $pth/libvbe.so libvbe.so
cp /media/lspace/install/arch/xorg.conf.usethis /etc/X11/xorg.conf
ln -s $pth/libextmod.so libextmod.so
ln -s $pth/libdbe.so libdbe.so
mkdir fonts
ln -s $pth/fonts/libfreetype.so fonts/libfreetype.so
ln -s $pth/libvgahw.so libvgahw.so
mkdir input
ln -s $pth/input/kbd_drv.so input/kbd_drv.so
ln -s $pth/input/mouse_drv.so input/mouse_drv.so
ln -s $pth/extensions/librecord.so extensions/librecord.so
ln -s $pth/extensions/libglx.so extensions/libglx.so
cp -r /usr/lib64/dri /usr/lib/xorg/modules/