Arch Linux

pittaxx

Member

Registered: 2010-10-16

Posts: 5

Strange bug with triplehead xorg setup using HD6870 and radeon driver

Firstly, during the boot all 3 monitors are working, although just cloned. However for grub/slim/X11 the primary monitor starts as disabled. If I switch to another shell from X11/Slim (aka ctrl+alt+F1) and back, the primary monitor gets enabled. It remains enabled during the login (slim -> xmonad) but not logout (xmonad->slim).

As you can see, I have my monitors set up veticaly, if I comment out the rotate option, the same error persists, however primary monitor does not get disabled during the logout (xmonad->slim). Additionaly with horizontal setup, trying to log in as root (which fails as root does not have .xinitrc) enables the primary monitor, while in vertical setup - it doesn't.

My 10-monitor.conf is as follows (display modes does not appear to do anything):

Section "Monitor"
  Identifier	"Monitor0"
  Option	"Primary" 	"True"
  Option    "Rotate" "Left"
EndSection

Section "Monitor"
  Identifier	"Monitor2"
  Option 	"RightOf" 	"Monitor0"
  Option	"Primary" 	"Flase"
  Option    "Rotate" "Left"
EndSection

Section "Monitor"
  Identifier	"Monitor1"
  Option 	"RightOf" 	"Monitor2"
  Option	"Primary" 	"Flase"
  Option    "Rotate" "Left"
EndSection

Section "Device"
  Identifier	"Card0"
  Driver	"radeon"
  Option	"Monitor-DVI-1" "Monitor0"
  Option	"Monitor-DVI-0" "Monitor1"
  Option	"Monitor-DisplayPort-1" "Monitor2"
EndSection

Section "Screen"
  Identifier	"Screen0"
  Device	"Card0"
  Monitor	"Monitor0"
  DefaultDepth	24
  SubSection "Display"
   # Modes	"1080x1920"
   # Modes	"1920x1080"
   # Virtual	 3240 1920
   # Virtual	5760 1080
  EndSubSection
EndSection

I've been messing with this for a while, but with no luck, as I have no idea what's happening here.

peewster

Member

From: Netherlands

Registered: 2011-07-18

Posts: 47

Re: Strange bug with triplehead xorg setup using HD6870 and radeon driver

I have the same card, and i'm using xrandr to configure the layout. Just install Xorg, Xorg -configure.

Then i have a small line added to my .xinitrc:

(sleep 2; xrandr --output DisplayPort-0 --left-of HDMI-0 --output DVI-1 --auto --right-of HDMI-0) &

This works very nice. You just have to adjust the interfaces (displayport, hdmi-0, dvi-1)

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PoC || GTFO