Soldato
I presume that I wasn't just lucky enough to get a black screen at 144hz@140fps_cap mode. At 160hz@155fps_cap mode I cannot play a single complete PUBG round (~30 minutes) without getting at least one black flick. So, it is not the OCing, it is some internal freesync/gsync bug, hopefully fixable via a firmware update.
And an important notice, neither windows 10 event viewer not radeon drivers records or detects that something is wrong. All happens inside the 27GP950 body.
Yep this is what I am getting, nothing is reported from Windows not even a disconnected sound plays.