# X.Org problem with 4 monitors



## n0n3 (May 12, 2013)

Hello.
I have a problem using 4 monitors in X.Org.
The most annoying thing is that 3 monitors work the way they should.
Changing card positions still allows to use 3 monitors without changing /etc/X11/xorg.conf
Problem arises when I add screen 3 to "Device" section, then only one card starts.

My configuration:
FreeBSD: 9.1-STABLE
Graphic cards: ATI Radeon RV505 and RV515

`uname -a`

```
FreeBSD n0n3 9.1-STABLE FreeBSD 9.1-STABLE #9 r249040: Wed Apr  3 18:23:09 CEST 2013     root@n0n3:/usr/obj/usr/src/sys/N0N3K  amd64
```

`# pciconf -lv`
http://pastebin.com/Fk5gm13G

`# cat /etc/X11/xorg.conf`
http://pastebin.com/QWrn4R5a

`# cat /var/log/Xorg.0.log`
http://pastebin.com/R6LUJBT7


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## wblock@ (May 12, 2013)

What is the problem?

I would remove all the references to Xinerama and the last three Screen sections, then set the first Screen's Virtual to 2560x2048.  Only two Device sections are needed, there are only two cards.


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## n0n3 (May 12, 2013)

If I remove 2 Device sections, then 4 monitors are working, but I have the same picture on both monitors connected to one graphic card (they are cloned). And I want "1 big desktop".


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## wblock@ (May 12, 2013)

Use xrandr(1) to set the monitor locations on the virtual screen.  Or that can be set with Position statements:


```
Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "HWP"
        ModelName    "2615"
        Option       "PreferredMode" "1920x1200"
        Option       "Position" "1280 0"
        Option       "Primary" "On"
EndSection

Section "Monitor"
        Identifier   "Monitor1"
        VendorName   "SAM"
        ModelName    "215"
        Option       "PreferredMode" "1280x1024"
        Option       "Position" "0 0"
        Option       "Primary" "Off"
EndSection
```


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## n0n3 (May 12, 2013)

Thank you, but xrandr is disabled when two cards are configured in X.Org.


```
[CMD=n0n3:~]n0n3% xrandr[/CMD] 
RandR extension missing
```


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## vermaden (May 13, 2013)

n0n3 said:
			
		

> Thank you, but xrandr is disabled when two cards are configured in X.Org.
> 
> 
> ```
> ...



In /etc/X11/xorg.conf file:

```
Section "ServerFlags"
  Option "RANDR" "on"
EndSection
```


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## n0n3 (May 16, 2013)

As far as I can tell I found problem in configuring X.org. Working 3 monitors: http://pastebin.com/9GLY7s8W, third monitor not working: http://pastebin.com/KPfXT5nc, `diff` of configs: http://pastebin.com/f7MpSAjf


```
--- xorg.conf_3monitors_ok      2013-05-16 01:36:17.788081917 +0200
+++ xorg.conf_2monitors_ko      2013-05-16 01:37:16.828072701 +0200
@@ -158,13 +158,13 @@
        Identifier  "Card2"
        Driver      "ati"
        BusID       "PCI:2:0:0"
+       screen 2
 EndSection

 Section "Device"
        Identifier  "Card3"
        Driver      "ati"
        BusID       "PCI:2:0:0"
-       screen 2
 EndSection
```


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