SLI and Ubuntu 8.04, trouble on multiple screens geforce 8600GT

[zackboll]

Hello,

I ended up getting a pair of 8600GT as I wanted to experiment with the CUDA compiler a little bit. I am having trouble getting SLI to work.

my current /etc/X11/xorg.conf looks like



# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 1.0 (buildmeister@builder26) Thu Feb 14 18:13:41 PST 2008

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildd@yellow) Tue Mar 4 20:28:57 UTC 2008

Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 1280 0
Screen 1 "Screen1" LeftOf "Screen0"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection

Section "Files"
RgbPath "/usr/X11R6/lib/X11/rgb"
EndSection

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

Section "ServerFlags"

# Removed Option "Xinerama" "0"
Option "Xinerama" "1"
EndSection

Section "InputDevice"

# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection

Section "Monitor"

# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "XXX M24EI4"
HorizSync 30.0 - 83.0
VertRefresh 56.0 - 71.0
Option "DPMS"
EndSection

Section "Monitor"

# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor1"
VendorName "Unknown"
ModelName "WDE LCM-19v5"
HorizSync 30.0 - 82.0
VertRefresh 56.0 - 76.0
Option "DPMS"
EndSection

Section "Device"
Identifier "Videocard0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce 8600 GT"
BusID "PCI:1:0:0"
Screen 0
EndSection

Section "Device"
Identifier "Videocard1"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce 8600 GT"
BusID "PCI:1:0:0"
Screen 1
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-0: 1920x1200 +0+0; DFP-0: 800x600 +0+0; DFP-0: 640x480 +0+0"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "0"
Option "TwinViewXineramaInfoOrder" "DFP-0"
Option "metamodes" "DFP-0: 1920x1200_60 +0+0; DFP-0: 800x600 +0+0; DFP-0: 640x480 +0+0"
Option "SLI" "off"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
# Removed Option "metamodes" "DFP-1: 1280x1024 +0+0; DFP-1: nvidia-auto-select +0+0"
# Removed Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
Identifier "Screen1"
Device "Videocard1"
Monitor "Monitor1"
DefaultDepth 24
Option "TwinView" "0"
Option "metamodes" "DFP-1: 1280x1024_60 +0+0"
Option "SLI" "off"
SubSection "Display"
Depth 24
EndSubSection




This is the one that works fine, as you can see from the config file, I have two displays, a 1280x1024 and a 1920x1200.

when I run the command

"nvidia-xconfig --sli=on"

I get this xorg.conf file




# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 1.0 (buildmeister@builder26) Thu Feb 14 18:13:41 PST 2008

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildd@yellow) Tue Mar 4 20:28:57 UTC 2008

Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 1280 0
Screen 1 "Screen1" LeftOf "Screen0"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection

Section "Files"
RgbPath "/usr/X11R6/lib/X11/rgb"
EndSection

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

Section "ServerFlags"

# Removed Option "Xinerama" "0"
Option "Xinerama" "1"
EndSection

Section "InputDevice"

# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection

Section "Monitor"

# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "XXX M24EI4"
HorizSync 30.0 - 83.0
VertRefresh 56.0 - 71.0
Option "DPMS"
EndSection

Section "Monitor"

# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor1"
VendorName "Unknown"
ModelName "WDE LCM-19v5"
HorizSync 30.0 - 82.0
VertRefresh 56.0 - 76.0
Option "DPMS"
EndSection

Section "Device"
Identifier "Videocard0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce 8600 GT"
BusID "PCI:1:0:0"
Screen 0
EndSection

Section "Device"
Identifier "Videocard1"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce 8600 GT"
BusID "PCI:1:0:0"
Screen 1
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-0: 1920x1200 +0+0; DFP-0: 800x600 +0+0; DFP-0: 640x480 +0+0"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "0"
Option "TwinViewXineramaInfoOrder" "DFP-0"
Option "metamodes" "DFP-0: 1920x1200_60 +0+0; DFP-0: 800x600 +0+0; DFP-0: 640x480 +0+0"
Option "SLI" "on"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
# Removed Option "metamodes" "DFP-1: 1280x1024 +0+0; DFP-1: nvidia-auto-select +0+0"
# Removed Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
Identifier "Screen1"
Device "Videocard1"
Monitor "Monitor1"
DefaultDepth 24
Option "TwinView" "0"
Option "metamodes" "DFP-1: 1280x1024_60 +0+0"
Option "SLI" "on"
SubSection "Display"
Depth 24
EndSubSection
EndSection





But then my second display, the 1280x1024 does not receive input. When I got to nvidia-settings, I see it disabled. I re-enable it in the GUI, save my xorg.conf, and restart X11 server, and then it still shows up as disabled.

Does SLI not work on multiple screens in Linux? I am really at a lost what to do here, any help/input would be appreciated.

Thanks,
Zack

[zackboll]

bump

[jrharvey]

when you go to the nvidia-settings, do you use sudo? To actually save the file you must be root.

[jrharvey]

BTW what do you think is better, 2 8600gt's or 1 8800gt?

[zackboll]

when you go to the nvidia-settings, do you use sudo? To actually save the file you must be root.

Yeah, I run nvidia-settings as root. I mainly got two 8600 GT because I am running 3 monitors and plan to add a fourth. In terms of stream processors, I think the 8800GT would be better, I believe it has 112. Each 8600GT has only 32 processors.

I don't believe nvidia driver support is very good for linux in 8XXX series and they do not support hardware accelerated video decoding like the 6XXX and 7XXX series. They do have a specialized compiler using CUDA though which is why I went with the 8XXX series.

Zack