Created attachment 18142 [details]
Log file with git master
With commit 8b8990917809b9a35c6e9c1b9e3b12ff81c6dbb3, radeon driver cannot detect the monitor connected to VGA-0. VGA-0 seems disconnected. If load_detection is set then lists the same modes with LVDS for VGA-0.
Reverting this commit fixes the problem. It detects monitor and shows correct modes.
01:05.0 VGA compatible controller: ATI Technologies Inc Radeon XPRESS 200M 5955 (PCIE)
Can you attach your log with that commit reverted?
Created attachment 18143 [details]
Log with 8b8990917809b9a35c6e9c1b9e3b12ff81c6dbb3 reverted
on Feb 26, 2017 at 00:54:34.
(provided by the Example extension).