I Found How To Make Dri Work On Imac G3 With R128 (suse 10.2)

there are two problems underlying the failure of X to correctly initialize the ATI r128 AGP card on G3 based iMacs
1) it loads AIGLX by default, which is not supported by R128 (look at the freedesktop.org website for detailed explanation)
2) Even though it can recognize the card as an AGP one, it can' t use it as such. At least with the default kernel configuration.
Thus the solution is:
1) to edit the xorg.conf file to disable AIGLX and to force usage of the card as a PCI (see the "Extensions" and "Device" sections
in my xorg.conf file below)

Maybe the SUSE maintainer might help to solve this problem:
If you read the Xorg.0.log after a failure to launch X with DRI it can be seen that the car is first seen at the PCI address 0:16:0,
then it corrects it to 0:1:0
However if in the Device section of xorg.conf i give the option "BusID" "0:1:0", the server fails and the following log states that
the card is at 0:16:0.

that means loosing AGP speed, i guess, any solution that you might implement in later releases?

P.S. Beware that metacity is part of the overall AIGLX infrastructure, thus running gnome might still cause you problems.
I am running KDE and my glxgears fps passed from 30, at the largest window size, to 700
I placed the option on AIGLX twice, as i wasn't sure where it had to go exactly, but it works anyway.

Cheers

Alessandro

# /.../
# SaX generated X11 config file
# Created on: 2007-03-06T22:38:29+0100.
#
# Version: 8.1
# Contact: Marcus Schaefer <sax@suse.de>, 2005
# Contact: SaX-User list <https://lists.berlios.de/mailman/listinfo/sax-users>
#
# Automatically generated by [ISaX] (8.1)
# PLEASE DO NOT EDIT THIS FILE!
#

Section "Files"
FontPath "/usr/share/fonts/misc:unscaled"
FontPath "/usr/share/fonts/local"
FontPath "/usr/share/fonts/75dpi:unscaled"
FontPath "/usr/share/fonts/100dpi:unscaled"
FontPath "/usr/share/fonts/Type1"
FontPath "/usr/share/fonts/URW"
# FontPath "/usr/share/fonts/Speedo"
FontPath "/usr/share/fonts/PEX"
FontPath "/usr/share/fonts/cyrillic"
FontPath "/usr/share/fonts/latin2/misc:unscaled"
FontPath "/usr/share/fonts/latin2/75dpi:unscaled"
FontPath "/usr/share/fonts/latin2/100dpi:unscaled"
FontPath "/usr/share/fonts/latin2/Type1"
FontPath "/usr/share/fonts/latin7/75dpi:unscaled"
FontPath "/usr/share/fonts/baekmuk:unscaled"
FontPath "/usr/share/fonts/japanese:unscaled"
FontPath "/usr/share/fonts/kwintv"
FontPath "/usr/share/fonts/truetype"
FontPath "/usr/share/fonts/uni:unscaled"
FontPath "/usr/share/fonts/CID"
FontPath "/usr/share/fonts/ucs/misc:unscaled"
FontPath "/usr/share/fonts/ucs/75dpi:unscaled"
FontPath "/usr/share/fonts/ucs/100dpi:unscaled"
FontPath "/usr/share/fonts/hellas/misc:unscaled"
FontPath "/usr/share/fonts/hellas/75dpi:unscaled"
FontPath "/usr/share/fonts/hellas/100dpi:unscaled"
FontPath "/usr/share/fonts/hellas/Type1"
FontPath "/usr/share/fonts/misc/sgi:unscaled"
FontPath "/usr/share/fonts/xtest"
FontPath "/opt/kde3/share/fonts"
# FontPath "unix/:7100"
InputDevices "/dev/gpmdata"
InputDevices "/dev/input/mice"
EndSection

Section "ServerFlags"
Option "AIGLX" "off"
Option "AllowMouseOpenFail" "on"
EndSection

Section "Module"
Load "dri"
Load "dbe"
Load "type1"
Load "freetype"
Load "extmod"
Load "glx"
Load "v4l"
EndSection

Section "InputDevice"
Driver "kbd"
Identifier "Keyboard[0]"
Option "Protocol" "Standard"
Option "XkbLayout" "us"
Option "XkbModel" "macintosh"
Option "XkbRules" "xfree86"
Option "XkbVariant" "intl"
EndSection


Section "InputDevice"
Driver "mouse"
Identifier "Mouse[0]"
Option "Buttons" "5"
Option "Device" "/dev/input/mice"
Option "Name" "USB Mouse"
Option "Protocol" "explorerps/2"
Option "Vendor" "Sysp"
Option "ZAxisMapping" "4 5"
EndSection


Section "Monitor"
DisplaySize 270 200
HorizSync 60-60
Identifier "Monitor[0]"
ModelName "Generic Monitor"
Option "DPMS"
VendorName "APP"
VertRefresh 75-117
UseModes "Modes[0]"
EndSection


Section "Modes"
Identifier "Modes[0]"
ModeLine "1024x768" 78.5 1024 1033 1129 1312 768 769 772 800 +hsync +vsync
Modeline "1024x600" 77.36 1024 1080 1192 1360 600 601 604 632
Modeline "1024x600" 67.63 1024 1080 1184 1344 600 601 604 629
Modeline "1024x600" 58.10 1024 1072 1176 1328 600 601 604 625
Modeline "1024x600" 48.96 1024 1064 1168 1312 600 601 604 622
Modeline "800x600" 62.40 800 825 905 1040 600 601 604 632 +hsync +vsync
Modeline "800x600" 53.14 800 840 928 1056 600 601 604 629
Modeline "800x600" 45.50 800 840 920 1040 600 601 604 625
Modeline "800x600" 38.22 800 832 912 1024 600 601 604 622
Modeline "768x576" 55.94 768 816 896 1024 576 577 580 607
Modeline "768x576" 48.71 768 808 888 1008 576 577 580 604
Modeline "768x576" 41.66 768 800 880 992 576 577 580 600
Modeline "768x576" 34.96 768 792 872 976 576 577 580 597
ModeLine "640x480" 49.9 640 653 717 832 480 481 484 514 +hsync +vsync
Modeline "640x480" 33.48 640 672 736 832 480 481 484 503
Modeline "640x480" 28.56 640 664 728 816 480 481 484 500
Modeline "640x480" 23.86 640 656 720 800 480 481 484 497
EndSection


Section "Screen"
DefaultDepth 16
SubSection "Display"
Depth 16
Modes "1024x768" "800x600" "768x576" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1024x768" "1024x600" "800x600" "768x576" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1024x768" "1024x600" "800x600" "768x576" "640x480"
EndSubSection
Device "Device[0]"
Identifier "Screen[0]"
Monitor "Monitor[0]"
EndSection


Section "Device"
BoardName "Rage 128 Pro TR (AGP)"
Driver "r128"
Identifier "Device[0]"
VendorName "ATI"
Option "ForcePCIMode" "true"
Option "UseFBDev" "true"
Option "SWCursor" "true"
Option "EnablePageFlip" "true"
Option "Accel" "true"
Option "Display" "CRT"
EndSection


Section "ServerLayout"
Identifier "Layout[all]"
InputDevice "Keyboard[0]" "CoreKeyboard"
InputDevice "Mouse[0]" "CorePointer"
Option "Clone" "off"
Option "Xinerama" "off"
Screen "Screen[0]"
EndSection


Section "DRI"
Group "video"
Mode 0660
EndSection

Section "ServerFlags"

Option "AIGLX" "off"
EndSection

Section "Extensions"

Option "Composite" "Disable"
EndSection