mga dualhead was Re: ports/116851

Warren Block wblock at
Thu Oct 25 10:44:00 PDT 2007

On Wed, 24 Oct 2007, Kevin Oberman wrote:

> Can anyone provide a clue as to how to get both monitors configured?
> Studying the xorg.conf man page has not made anything obvious to me.

I've experimented a bit more with my configuration.  As I mentioned 
earlier, you can assign monitors to outputs in the Device section. 
What I found was that specifying HorizSync or VertRefresh in the Monitor 
section caused problems.  What works:

Section "Monitor"
         Identifier   "Monitor0"
         VendorName   "PNR"
         ModelName    "Planar PE190"
         Option       "Position" "1024 0"

Section "Monitor"
         Identifier   "Monitor1"
         VendorName   "Philips"
         ModelName    "Philips 150B3"
         Option       "Position" "0 0"

Section "Device"
         Identifier  "Card0"
         Driver      "mga"
         VendorName  "Matrox Graphics, Inc."
         BoardName   "MGA G400/G450"
         BusID       "PCI:1:0:0"
         Option      "HWcursor"                  "off"
         Option      "AGPMode"                   "4"
         Option      "Monitor-VGA1"              "Monitor0"
         Option      "Monitor-VGA2"              "Monitor1"

This runs both monitors at their DDC-detected resolution.  In my case, 
that's 1280x1024 for Monitor0 and 1024x768 for Monitor1.  If I tried to 
explicitly set a Mode for Monitor1, it went to 640x480.

'Option "Position" is not used' is still in the log, although it also 
shows the positions set for both monitors.

-Warren Block * Rapid City, South Dakota USA

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