Cracked this. The solution was that I needed to specify the correct
driver ("radeon") in the xorg conf file to use the open source driver,
e.g.
Section "Device"
Identifier "aticonfig-Device[0]-0"
Driver "radeon"
BusID "PCI:1:0:0"
EndSection
All the other bits from the conf file I could keep the same as before.
On Wed, Sep 19, 2018 at 10:41 AM Richard G <grainger at gmail.com> wrote:
>
> I have an unusual use case. I wonder if anyone can help. We use a PC
> with 8 HDMI outputs for powering a video wall in an operations centre.
> We use two Matrox video cards, each with 4 outputs. "lspci" reports
> these cards as" [AMD/ATI] Cape Verde PRO [FirePro W600]".
>
> On an older version of CentOS 7, I used the proprietary AMD/ATI
> driver. This had a utility (I roorget the name) that generated a
> working xorg.conf file. I could them throw up the
> "matchbox-window-manager" on each monitor in turn using
> "DISPLAY=:0.0", "DISPLAY=:0.1" etc and then throw up a full-screen
> chrome web browser in kiosk mode on each monitor after that. This all
> worked great.
>
> In a recent version of CentOS 7, this all broke. The proprietary
> driver no longer works. The good news is that the open source driver
> seems to work fine with multi-monitor in Gnome for example.
>
> My only issue is that I don't want to use Gnome across multiple
> monitors. I want to use matchbox-window-manager or similar, and
> specify individual X screen (":0.0", ":0.1" etc). How do I generate
> an xorg.conf file with the new open source drivers? Am I doing this
> all wrong?
>
> Thanks!