I spent far more time last week making two monitors not work than I did making them work, so hereâ€™s I few things I have learnt:
- Donâ€™t use the â€œnvâ€ driver. I couldnâ€™t get it to drive two screens at once, much as I would have liked it to.
- Donâ€™t use â€˜Option â€œConnectedMonitorâ€ â€œdfpâ€â€˜ with the â€œnvidiaâ€ driver. I did RTFM rather too well and put that in as a hint to the driver. While ever it was in the xorg.conf file, only one screen at a time would work.
The eventual solution was, surprise, surprise, to download the latest version of the Nvidia driver â€” which was released partway through this epic battle â€” and follow its instructions to the letter â€” including removing existing Ubuntu packages as directed. I donâ€™t know whether the driver had improved or my technique had improved by the time I tried that third version, but it worked for me.
Of course, the first thing I did when both screens worked was see how many 80-column Emacs frames would fill the screens: over 600 lines of Emacs visible at once, now that makes it all worthwhile!
I started out using the two monitors as separate X screens but Iâ€™m now using Twinview so itâ€™s easy to Alt-Tab amongst the Emacs frames. The X startup log shows that X thinks the combined screen is too wide to be allowed, so it starts at a lower resolution, but once Iâ€™ve logged in, I can jigger the â€œNVIDIA X Server Settingsâ€ tool to get it back to itâ€™s highest resolution.
In keeping with the long tradition of filling the Internet with example configuration files that are all purported to work but are all somehow puzzlingly different, hereâ€™s the xorg.conf file thatâ€™s working for me:
# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildmeister@builder26) Mon Feb 26 23:38:28 PST 2007
Screen 0 â€œScreen0â€³ 0 0
InputDevice â€œKeyboard0â€³ â€œCoreKeyboardâ€
InputDevice â€œMouse0â€³ â€œCorePointerâ€
Option â€œXineramaâ€ â€œ0â€³
# generated from default
Option â€œProtocolâ€ â€œautoâ€
Option â€œDeviceâ€ â€œ/dev/psauxâ€
Option â€œEmulate3Buttonsâ€ â€œnoâ€
Option â€œZAxisMappingâ€ â€œ4 5â€³
# generated from default
# HorizSync source: edid, VertRefresh source: edid
ModelName â€œApple Cinema HDâ€
HorizSync 49.3 – 98.5
VendorName â€œNVIDIA Corporationâ€
BoardName â€œQuadro FX 1500â€³
Option â€œTwinViewâ€ â€œ1â€³
Option â€œmetamodesâ€ â€œDFP-0: 2560Ã—1600 +2560+0, DFP-1: 2560Ã—1600 +0+0; DFP-0: 1280Ã—800 +1280+0, DFP-1: 1280Ã—800 +0+0â€³
Modes â€œ1600Ã—1200â€³ â€œ1280Ã—1024â€³ â€œ1024Ã—768â€³ â€œ800Ã—600â€³ â€œ640Ã—480â€³