In Linux Mint 13.0 systems (ubuntu 12.04 based and with 3.2.x kernels) the Nouveau driver is now the only chance to use old nvidia cards (NVS 280 AGP or Quadro4 550 XGL AGP) for dual-head (two monitor displays).

The xorg.conf file enclosed and the method explained in this page may help to you configure old nvidia cards.

At the end of this process you will be able to use the control panel to fix the desired resolution in your dual head system

Enjoy it.

-------------

Fix Update, September2012: After a Linux Mint 13.0 Maya update (september 19th) right monitor resolution regressed to default (1280x1024). I have applied a small modifications to the previously presented xorg.conf file allowing to work again as is (a few lines describing right monitor previously skipped).

Enjoy it.

----------------------------------

Update June'2012: I Updated to Linux Mint 13.0 Maya just to discover: 

With Linux Mint 13.0 (ubuntu 12.04 based and with 3.2.x kernels) the previously banned Nouveau driver is now the only chance to use old nvidia cards (NVS 280 AGP or Quadro4 550 XGL AGP) for dual-head (two monitor displays). With nvidia driver you will get problems to set resolutions.

The original (old) configuration xorg.conf file works as before with my old nvidia cards.

Enjoy it.

------------------------------------

Update March'2012: I swaped my card by a Nvidia Quadro4 550 XGL AGP: It works fine and it is a bit faster. It may be used with the same original xorg.conf file.

--------------------------

With Linux Mint 12.0 (ubuntu 10.12 based and with 3.0.x kernel) the nvidia 96-updates driver is mandatory for dual-head in old cards. Don't use the proposed nouveu driver with old nvidia cards in Mint 12.0 and related Ubuntu. You will end on a black screen and you will not be able to control your system.

--------------------------------

Setting-up a new video card or monitor is still the worst side of linux, both for beginners but also for advanced users. It is very easy to set the most common monitors in most linux systems but I have lost several hours (googling and nn rebooting) every time I have tried to use large o special monitors.

Here I post my current working xorg.conf files that may solve most problems for users of 1080p (1920x1080, HDTV based) monitors. They worked for me with old ati cards (ati rage 128 pro) and old nvidia (nvidia quadro NVS280 and Quadro4 550 XGL AGP) both with nouveau free driver and nvidia propietary driver.

Over the last year I moved all my instalations to the mainstream Linux Mint 12 as Linux Mint debian has broken my video settings and later my keyring doing package updates.

Nouveau driver no longer works fine with dual-head in old cards (Quadro NVS 280 AGP and Quadro4 550 XGL AGP) usign newer kernels ( > 2.6.37 - 3.0.0.x  and newer). After expending 20+ hours i only got 1 screen + 40% of the right screen visible (the right working very slow and with only 1024x1080 real pixels available !). No way. 

Conclusion: With newer kernels (3.0.0.x use the 96-updates driver. They work fine (see part 3 of 3)

# Experts only: Copy and paste the modeline lines and add the video modes and maybe your are done for a single monitor installations with many old video card. It have worked for me for ati-nvidia cards. 
#

This Nouveau xorg.file is for a dual screen (xinerama) system but can be applied to any nvidia configuration using the free nouveau driver. Use nouveau if you require it, but it is said that nvidia drivers provide much better performance (not personally tested).

With nvidia legacy driver (96.43.18 and 96 updates) the modeline definition is not necesary (see part 3 of 3)

Remember to change the keyboard layout and language/country (in blue in my setup: es = Spanish (es, es_ES or ca_ES). Fix following your needs.

Dual Monitor - Nouveau driver - Nvidia quadro NVS-280 dual head AGP (VGA-DB15) and two 1080p monitors (acer 23'' 1920x1080, db15 connectors) and Linux Mint Debian 2.6.32

 

Nvidia quadro NVS 280 AGP (or Nvidia Quadro4 550 XGL) is a few year old model dual head video card that can be still found as a new product in internet shops (pe. as an HP OEM part). Used in CAD workstations is still a very good high resolution 2D card, low power and fanless.

It only works with the nouveau open driver, and propietary nvidia legacy drivers (version up to 96.43.18). 

Don't try/upgrade to newer drivers (as I did) that deliver much better performances: they will not even detect your previously working card. You will end in a deadlock: black screen with a top-left corner flashing cursor. As usual, by booting in 'safe mode' you may execute 'dmesg | less' and you will be able to see the causes of your pains along the listing. 

Quick fix for the video deadlock: Create a short xorg.conf writting 'nouveau' as the driver in place of nvidia. You may use 'nvidia-xconfig' to build the file from scratch for you, but remember to replace with nouveau. Reboot and you will be able work in Gnome and use 'Synaptic' to change the drivers packages to the required version (in this case legacy 96.43.18)

1.- make a copy of your xorg.file cp /etc/X11/xorg.conf /etc/X11/xorg.conf.my

2.- Save as /etc/X11/xorg.conf the following content

# nvidia-xconfig: X configuration file generated by nvidia-xconfig and hand editted
# nvidia-xconfig: version 1.0 (pbuilder@windlord) Sun Jun 13 06:03:17 UTC 2010

Section "ServerFlags"
# Option "NoTrapSignals"
# Option "DontVTSwitch"
## Option "DontZap" "off"
# Option "DontZoom"
# Option "DisableVidModeExtension"
# Option "AllowNonLocalXvidtune"
# Option "DisableModInDev"
# Option "AllowNonLocalModInDev"
# Option "blank time" "10" # 10 minutes
# Option "standby time" "10"
# Option "suspend time" "30"
# Option "off time" "60"
# Option "EstimateSizesAggresively" "0"
# Option "AutoEnableDevices" "false"
# Option "AutoAddDevices" "false"
## Option "AllowEmptyInput" "false"
EndSection

# **********************************************************************
# Module section ( Dynamically loadable modules )
#_______________________________________________________________________


# Extensions ( Extension enabling )
#_______________________________________________________________________

Section "Extensions"
Option "Composite" "disable"

# disable composition as is slow on old video cards

Section "ServerLayout"
Identifier "Layout0"
Screen "Screen0"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection


Section "Files"
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"
Option "AutoRepeat" "500 30"
# Option "Xleds" "1 2 3"
# Option "XkbDisable"
# Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "es"
Option "XkbOptions" "terminate:ctrl_alt_bksp"
EndSection

Section "Monitor"
Identifier "Monitor0"
VendorName "Acer"
ModelName "AT2356"
HorizSync 31.5 - 80.0
VertRefresh 60
DisplaySize 510 287
# Option "UseEdidFreqs" "1"
Option "DPMS"
# Option "ReducedBlanking"
# Modeline "1920x1080_60.00" 172.80 1920 2040 2248 2576 1080 1081 1084 $
ModeLine "1080p" 148.50 1920 2012 2068 2200 1080 1082 1088 1125
# ModeLine "1080i" 74.52 1920 1952 2016 2208 1080 1084 1096 1126 interlace
# ModeLine "720p" 73.825 1280 1320 1368 1640 720 722 724 751
#Option "ReducedBlanking" "TRUE"
#Option "ExactModeTimingsDVI" "TRUE"
#Option "ModeValidation" "NoDFPNativeResolutionCheck"
EndSection
#

Section "Monitor"
Identifier "Monitor1"
VendorName "Acer"
ModelName "AT2356"
HorizSync 31.5 - 80.0
VertRefresh 60
DisplaySize 510 287
# Option "UseEdidFreqs" "1"
Option "DPMS"
# Option "ReducedBlanking"
# Modeline "1920x1080_60.00" 172.80 1920 2040 2248 2576 1080 1081 1084 $
ModeLine "1080p" 148.50 1920 2012 2068 2200 1080 1082 1088 1125
# ModeLine "1080i" 74.52 1920 1952 2016 2208 1080 1084 1096 1126 interlace
# ModeLine "720p" 73.825 1280 1320 1368 1640 720 722 724 751
# Option "ReducedBlanking" "TRUE"
# Option "ExactModeTimingsDVI" "TRUE"
# Option "ModeValidation" "NoDFPNativeResolutionCheck"
Option "PreferredMode" "1920x1080_60.00"
EndSection

#
Section "Device"
Identifier "Device0"
VendorName "NVIDIA Corporation"
Driver "nouveau"
# Driver "nvidia"
# Driver "nv"
Option "GLXVBlank" "true"
EndSection

#
Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "True"
Option "MetaModes" "nvidia-auto-select, nvidia-auto-select"
Subsection "Display"
Depth 8
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
Subsection "Display"
Depth 16
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
Subsection "Display"
Depth 24
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
# Subsection "Display"
# Depth 32
# Modes "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
# Modes "2560x1600" "2048x1536" "1920x1440" "1920x1200" "1920x1080" "1680x1050" "1600x1200"
# EndSubsection
EndSection

# end of /etc/X11/xorg.conf (xorg X Window System server configuration file)
#


3.- Type [Ctrl]+[Alt]+[<- backspace] to restart your X11 graphic subsystem

4.-In the 'Control Panel', select 'Monitors/Display' and set the final layout and resolution.

5.- I hope you are done !

---

Working system 

1. Dell GX-260 SFF (P4-2.66GHz, 2GB RAM) Linux Mint 12.0; small and quiet
   1. Video card nvidia low profile Quadro4 550 XGL AGP + dual-head cable; ebay
   2. Two Acer AT2356 1080p 23'' TFT monitors; large desktop: I'm an old guy
2. Dell GX-260 (P4-2.66GHz, 2GB RAM) Linux Mint 12.0; small and quiet
   1. Video card nvidia low profile Quadro NVS 280 AGP + dual-head cable (new HP oem card) ; ebay
   2. Now beheaded with only one 19'' Dell 1905FP.

---

The previous xorg.conf, working in Linux Mint 12.0 and older versions

The rest of the tutorial than for newer Linux int systems. Just a few lines are changed with a few new parameters; probably the new version will work without a glitch as xorg will neglect these minor changes (I have not personally tested).

xorg.xconf file to the copied almost 'as is' to /etc/X11/xorg.conf

# nvidia-xconfig: X configuration file generated by nvidia-xconfig and hand editted
# nvidia-xconfig: version 1.0 (pbuilder@windlord) Sun Jun 13 06:03:17 UTC 2010

Section "ServerFlags"
# Option "NoTrapSignals"
# Option "DontVTSwitch"
## Option "DontZap" "off"
# Option "DontZoom"
# Option "DisableVidModeExtension"
# Option "AllowNonLocalXvidtune"
# Option "DisableModInDev"
# Option "AllowNonLocalModInDev"
# Option "blank time" "10" # 10 minutes
# Option "standby time" "10"
# Option "suspend time" "30"
# Option "off time" "60"
# Option "EstimateSizesAggresively" "0"
# Option "AutoEnableDevices" "false"
# Option "AutoAddDevices" "false"
## Option "AllowEmptyInput" "false"
EndSection

# **********************************************************************
# Module section ( Dynamically loadable modules )
#_______________________________________________________________________


# Extensions ( Extension enabling )
#_______________________________________________________________________

Section "Extensions"
# Option "Composite" "enable"
EndSection


Section "ServerLayout"
Identifier "Layout0"
Screen "Screen0"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
EndSection


Section "Files"
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"
Option "AutoRepeat" "500 30"
# Option "Xleds" "1 2 3"
# Option "XkbDisable"
# Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "es"
Option "XkbOptions" "terminate:ctrl_alt_bksp"
EndSection

Section "Monitor"
Identifier "Monitor0"
VendorName "Acer"
ModelName "AT2356"
HorizSync 31.5 - 80.0
VertRefresh 60
DisplaySize 510 287
# Option "UseEdidFreqs" "1"
Option "DPMS"
# Option "ReducedBlanking"
# Modeline "1920x1080_60.00" 172.80 1920 2040 2248 2576 1080 1081 1084 $
ModeLine "1080p" 148.50 1920 2012 2068 2200 1080 1082 1088 1125
# ModeLine "1080i" 74.52 1920 1952 2016 2208 1080 1084 1096 1126 interlace
# ModeLine "720p" 73.825 1280 1320 1368 1640 720 722 724 751

Option "ReducedBlanking" "TRUE"
Option "ExactModeTimingsDVI" "TRUE"
Option "ModeValidation" "NoDFPNativeResolutionCheck"
EndSection

Section "Device"
Identifier "Device0"
Driver "nouveau"
# Driver "nvidia"
# Driver "nv"
VendorName "NVIDIA Corporation"
EndSection

Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "True"
Option "MetaModes" "nvidia-auto-select, nvidia-auto-select"
Subsection "Display"
Depth 8
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
Subsection "Display"
Depth 16
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
Subsection "Display"
Depth 24
Modes "1080p" "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
EndSubsection
# Subsection "Display"
# Depth 32
# Modes "1920x1080_60.00" "1440x900" "1280x1024" "1024x768" "800x600"
# Modes "2560x1600" "2048x1536" "1920x1440" "1920x1200" "1920x1080" "1680x1050" "1600x1200"$
# EndSubsection
EndSection

# end of /etc/X11/xorg.conf (xorg X Window System server configuration file) #