LG 27GL850-B Issue

ubersonic · 9 Oct 2019 at 17:22

Hey all, wondering if anyone else is experiencing this issue or if it's a generic one others have come across.

Got my new LG 27GL850-B, all working great, however there's one issue. If connected via HDMI it works fine either at 144Hz no-Sync or 100Hz FreeSync (sadly it can't do 144Hz FreeSync over HDMI, something LG hid from buyers at launch).

But if connected via DisplayPort then it shows horrid flickering, almost like the backlights are pulsing on/off, it does this no matter what Hz or Sync settings are used, but if you turn on the "Just Scan" option in the aspect ratio settings then it works fine, however that option is disabled if Adaptice Sync is enabled.

Anyone else come across this? Any ideas?

nomadd · 9 Oct 2019 at 17:29

ubersonic said:
Hey all, wondering if anyone else is experiencing this issue or if it's a generic one others have come across.

Got my new LG 27GL850-B, all working great, however there's one issue. If connected via HDMI it works fine either at 144Hz no-Sync or 100Hz FreeSync (sadly it can't do 144Hz FreeSync over HDMI, something LG hid from buyers at launch).

But if connected via DisplayPort then it shows horrid flickering, almost like the backlights are pulsing on/off, it does this no matter what Hz or Sync settings are used, but if you turn on the "Just Scan" option in the aspect ratio settings then it works fine, however that option is disabled if Adaptice Sync is enabled.

Anyone else come across this? Any ideas?

Is HDR on?

Only reason I mention it is RTings mentioned this in their review: "While trying to measure the HDR real scene peak brightness, we encountered a bug, and the monitor started to flicker. We don't know why this happened, and we didn't encounter it with our other HDR tests."

ubersonic · 9 Oct 2019 at 18:40

Nope HDR is off (and the colour depth set to 8bit not 10bit).

It's quite odd.

ubersonic · 10 Oct 2019 at 00:29

Update: Seems it may actually be an issue either with my GPU or drivers, as I tried connecting the screen via DisplayPort to my old Dell M6600 laptop and it not only did it work fine at 144Hz, it even let me enable FreeSync which I didn't even know my 8 year old laptop supported lol.

That's also thrown up more to the issue than I realised as it ran at a solid 144Hz with FreeSync enabled wheras connected to my current Vega based system it would fluctuate between 144Hz/72Hz on the monitor OSD in addition to the flickering.