AnsweredAssumed Answered

Frequent Black Screen and loss of sound with LG 34UC88 or 34UM88 with powercolor 390 via DisplayPort

Question asked by pinkyfloyduk on Apr 20, 2016
Latest reply on Mar 26, 2017 by fps120

The Issue:

Frequent black screens (blackouts) with loss of sound when playing intensive 3d games with monitor set to 1.2 displayport (freesync off) OR with monitor set to freesync on (displayport version cannot be selected when freesync is ON).  Preferred color depth in driver UI set to either '8' or '10'.


Video of Issue:

LG 34UC88 - Displayport Freesync Issues - Disconnects - Blank Screen and sound cutting out - Vid 1 - YouTube


When does issue not occur:

When monitor is set to displayport 1.1  OR when preferred color depth in AMD Crimson driver UI set to '6'


My System:

3770k @ 4.3ghz

16gb DDR3 Corsair Dominator RAM

Powercolor PCS+ R9 390


What I did to test the issue:

Tested with 2 monitors from the same family (34UC88 and 34UM88)

Tried 3 different branded high quality 1.2 displayport cables (including the recommended Accell)
Re-installed the monitor drivers several time
Uninstalled the AMD GPU driver and did a clean install

Tried an earlier driver 16.1 branch
Tried 2 different games (The Witcher 3, Rise of the Tomb Raider)
Reset the monitor to factory settings several times
Used the display port cables with a different, non-freesync monitor and the above games @120hz for several days (no issues were observed)
System and components have previously been driving 2 x 1080p monitors (one @120hz) with no issues

Turned off ULPS

Turned off Power Efficiency

Locked core GPU clocks to max

Increased power settings +50%


Comments:  Please note, I don't currently have a monitor to do any testing but I have a 34UC88 on backorder I wanted to put this information on here as blackouts seem like a really common issue with these large panel, high hz, high res monitors.


Does anyone have the slightest idea of what is going on here?  I found an obscure post online where someone with a different brand of monitor and GPU (was a 390 though) had flickering and blackout issues and found that changing the preferred color depth to 6 fixed it.  I did the same and it appeared also to fix it (I played Witcher 3 for 30 mins afterwards and didn't get one blackout, where previously I was getting between 10-20 blackouts per minute).


I loved the monitor, I have another one coming but I won't keep it unless I can get to the bottom of things.


Would love to hear your thoughts!