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            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Same output (DisplayPort) is used in multi-head configuration for different Devices/Displays"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=99103#c7">Comment # 7</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Same output (DisplayPort) is used in multi-head configuration for different Devices/Displays"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=99103">bug 99103</a>
              from <span class="vcard"><a class="email" href="mailto:Stefan.LAUTERWASSER@thalesgroup.com" title="Stefan.LAUTERWASSER@thalesgroup.com">Stefan.LAUTERWASSER@thalesgroup.com</a>
</span></b>
        <pre>Created <span class=""><a href="attachment.cgi?id=132133" name="attach_132133" title="working multi-head configuration with 8 monitors">attachment 132133</a> <a href="attachment.cgi?id=132133&action=edit" title="working multi-head configuration with 8 monitors">[details]</a></span>
working multi-head configuration with 8 monitors

I am not sure, but I think these entry fixed the issue more or less:

Section "Device"
    Option          "ZaphodHeads" "DisplayPort-X"
EndSection

Also new entries are:

Section "Module"
    Load            "dri"
    Load            "extmod"
EndSection

Section "DRI"
    Mode            0666
EndSection

Section "Device"
    Option          "AccelMethod" "glamor"
    Option          "DRI3" "True"
    Option          "TearFree" "True"
EndSection

I also have to enable the the monitors manually via xrandr after x start-up -
don't know why:

DISPLAY=:0.4 xrandr --output DisplayPort-1-4 --auto
DISPLAY=:0.5 xrandr --output DisplayPort-1-5 --auto
DISPLAY=:0.6 xrandr --output DisplayPort-1-6 --auto
DISPLAY=:0.7 xrandr --output DisplayPort-1-7 --auto</pre>
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