[Xorg] Dual-head setup with multiple devices

Kingtiger01 · 01-05-2016, 01:25 AM

To make this short...

I have a box with 2 VGA Adaptors, both are AMD and both can run the open-source Radeon Driver.
Each have a monitor connected to there DVI-I-0 port(dvi port 0).

devices are as follows:
1. R9 280x(Tahiti) PCI:1.x
2. HD5xxx(Evergreen) PCI;6.x

I havent done a dual-head setup in a very long time and the conf.d makes things a little more confusing while helping making things more modular.

i cant figure out how to configure these, i can get X to detect the devices but it doesnt say anything about there screens or independence at all. just keeps plowing through to defaults on 1.

Please help me, LQ, your my only hope!

Keith Hedger · 01-05-2016, 10:34 AM

The 'prefered' way to do this now is to use xrandr, for instance on my system

Code:

keithhedger@LFSHal:~-> xrandr
Screen 0: minimum 320 x 200, current 1920 x 1980, maximum 8192 x 8192
DVI-0 connected 1440x900+0+0 (normal left inverted right x axis y axis) 408mm x 255mm
   1440x900      59.89*+  74.98  
   1280x1024     75.02    60.02  
   1280x960      60.00  
   1152x864      75.00  
   1024x768      75.08    70.07    60.00  
   832x624       74.55  
   800x600       75.00    60.32    56.25  
   640x480       75.00    60.00  
   720x400       70.08  
HDMI-0 disconnected (normal left inverted right x axis y axis)
VGA-0 connected 1920x1080+0+900 (normal left inverted right x axis y axis) 477mm x 268mm
   1920x1080     60.00*+
   1680x1050     59.95  
   1280x1024     75.02    60.02  
   1440x900      59.89  
   1280x960      60.00  
   1280x800      59.81  
   1152x864      75.00  
   1280x720      60.00  
   1024x768      75.08    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   640x480       75.00    72.81    66.67    60.00  
   720x400       70.08

And is set up on starting the XServer with:

Code:

xrandr --output VGA-0 --below DVI-0 --mode 1920x1080

Kingtiger01 · 01-07-2016, 09:53 PM

this doesnt work with multiple devices. as it only detects one device.

Keith Hedger · 01-08-2016, 05:31 AM

MAybe a problem with one of your cards then as, as you can see I have two different devices, both of which are detected properly.

Kingtiger01 · 01-12-2016, 10:24 PM

Normally i would agree, but ive managed a independant dual-head through some wierd configuration once... and only once. cant get xinerama or the like to work

ill give more info.

lspci | grep VGA

Code:

01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Tahiti XT [Radeon HD 7970/8970 OEM / R9 280X]
06:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Juniper XT [Radeon HD 5770]

xrandr

Code:

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
DisplayPort-0 disconnected (normal left inverted right x axis y axis)
HDMI-0 disconnected (normal left inverted right x axis y axis)
DVI-0 disconnected (normal left inverted right x axis y axis)
DVI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 435mm x 239mm
   1920x1080     60.00*+
   1680x1050     59.88  
   1280x1024     75.02    60.02  
   1440x900      59.90  
   1280x960      60.00  
   1280x720      60.00  
   1024x768      75.08    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   640x480       75.00    72.81    66.67    60.00  
   720x400       70.08

xorg.0.log
xorg.0.log on Gist < with serverlayout disabled, so monitor layout is not set... screen #2(Acer) is powered(active light is on, and backlight is lit). but there is no activity and nothing in xrandr. screen #1(AOC) is fine though. i cant make heads or tails of it.