Odd LG OLED TV behavior (a *problem)

[Psittac]

I have had some weird behavior trying to run two different 4k LG OLED displays (basically TV's) on my main machine.  I'm making this as an information post or spitballing to what is going on.

 

A number of months ago I got a refurbished LG 48GQ900-B 48" Ultragear UHD OLED and it died pretty quickly, the OSD was going wonky and eventually it was acting up when connected to nothing.  So I got in contact with LG and they said to return it, when I initiated the return and after a lot of back and forth they said to send a picture of the power cable cut and keep it.  So I bought a new power cable with the hopes of fixing it some day, took it apart had a friend look at it etc etc but nothing ever materialized and it sat in the closet.  I replaced it with a Sony BRAVIA XR 42” Class A90K and everything was mostly fine.  Every once in a while it would have a hard time connecting but was fine after it made a good connection.  Well the past week or so it started acting like another display was hooked up, go black then come back.  I could find no pattern for this as it could happen every 5 minutes or go a couple hours without doing this.  I got to thinking it could be a GPU issue and was going to swap my 2080 for my 3080 and see if it helped, but my friend said that I should DDU the drivers, which I did, borked the system and just reinstalled fresh (it's been a number of years on the same install, was win10 previously).  Now with a fresh install of windows this Sony appears to be fine.

 

So I decided to pull the LG out and put it back together and it's been running for almost 4 hours now on a second system with zero issues......

 

I'm not in the clear yet but so far everything is looking good.

 

I'm thinking it was some kind of driver/software issue?  What I don't get is before both of these I had a 32" 4k 60hz HDR monitor in place as my main monitor with zero issues for several month's, then immediately the LG acted up and the Sony took a few month's of gradually getting worse.  I did everything short of main PC hardware and software changes including cables and settings within the monitors.

 

Any thoughts?

 

Also I'm having another display issue today since the fresh OS install but I'm going to make another post about that.

[porina]

Even at only 4k60 you need a good HDMI cable. One that is marginal can result in random dropouts. If you ever go 4k120 it gets worse.

 

With some gaming only, I had weird dropouts which I eventually found was due to some kind of interaction between VRR and the LG TV. It seemed like the TV was occasionally switching between gaming and non-gaming mode. That went away when I unchecked the "use G-sync for windowed apps" or something like that. It is default off even with certified displays connected. I was playing borderless full screen when there were the problems. It didn't happen with exclusive full screen since I guess the display never has to change mode.

[Psittac]

53 minutes ago, porina said:

Even at only 4k60 you need a good HDMI cable. One that is marginal can result in random dropouts. If you ever go 4k120 it gets worse.

 

With some gaming only, I had weird dropouts which I eventually found was due to some kind of interaction between VRR and the LG TV. It seemed like the TV was occasionally switching between gaming and non-gaming mode. That went away when I unchecked the "use G-sync for windowed apps" or something like that. It is default off even with certified displays connected. I was playing borderless full screen when there were the problems. It didn't happen with exclusive full screen since I guess the display never has to change mode.

Good to know thank you.

 

What do you recommend for a good HDMI cable?  I have 3x 10ft "8K" cables because I unknowingly bought the same exact cable recently.  But I've done it with multiple cables that worked on 4k60hz.  The odd thing is that even turning it down to 4k25hz didn't help recently.  I don't know, I should invest in a few different HDMI cables incase it starts acting up again.  Next I'm thinking of upgrading the gpu.

[porina]

I can't suggest a specific cable other than you can try to shop for certified ones. It is still possible the problem might not be the cable but I don't have anything further to add.

[Psittac]

So far what I know is it wasn't a software issue because it started doing it again.  I just updated the vbios and enabled resizeable bar so hopefully that fixes it.  After that I will be getting a different HDMI cable, while I've used two brand new ones they're both from the same manufacturer, but if that isn't it the only thing left is my gpu.

 

*it's doing it while just looking at a browser, also I have the third monitor completely unplugged

[Psittac]

Now today the LG is doing it again

 

 

 

I don't know what the issue is and I'm kind of at a loss.  Both of them are acting funny and I don't know what the problem is.  The video is after it started messing up and I switched it to 1080p 30hz and it still did it.  I turned it off and back on and I'm going to see if it acts up again.

 

I thought the Sony would be better but no luck.... It's the only monitor connected right now and it will barely even get a signal.  After 10 minutes sometimes it turns on.

 

I have all VRR off on both (*I'm thinking I missed VRR within the display on the LG, only did OS side turning off)

 

*maybe I should use a roku or nvidia shield for a while on both and see if it still acts up

[porina]

I haven't seen anything like that. The flickering is on the LG, is it same on the Sony or a different problem? I see in OP it was stated the LG worked on a different system, so I am wondering if it is the system more than the display. I feel it is still worth trying a different HDMI cable. I can't remember the names but get one certified for 4k120 and it should be fine at 4k60.

[Psittac]

6 hours ago, porina said:

I haven't seen anything like that. The flickering is on the LG, is it same on the Sony or a different problem? I see in OP it was stated the LG worked on a different system, so I am wondering if it is the system more than the display. I feel it is still worth trying a different HDMI cable. I can't remember the names but get one certified for 4k120 and it should be fine at 4k60.

So I'm just banging my head against a wall.  They're both acting up on different systems in slightly different ways.  Sometimes they act the same by just going black for a few seconds, sometimes this LG does like in that video.  I changed some settings around and now the LG is working for now, I turned off HDR and went to 8b color depth as well as YCbCr422 and it appears to be behaving.  On the Sony I actually spent some time tinkering with the settings to find the highest bandwidth it would run at, or rather the highest of each setting.  And that thing.... now.... it only likes 1080p 60hz SDR 8b color depth, I think I got it to go 10b but everything else and it would crap the bed.

 

What I really don't get is this LG was acting crazy when literally hooked to nothing, just power and no inputs after it got really bad (even the OSD was wigging out), so I shut it down and took it apart and let it sit for month's.  Now it's doing what I've described.

 

I apologize for all of the vagueness in my post, it's because I don't know anything about monitors, but I do know about turning thing's down in settings then back up, like overclocking but not really, finding the weakest setting.  I'm at a complete loss.

 

One possibility is I'm hitting the theoretical limit of my gpu ports by trying to throw everything at it?  They're not the newest standards. Another strong issue is the cables, I was going to order some from infinite cables today but got sidetracked.

[Psittac]

Ok, I guess this will just be a log for myself really, can't expect anyone to read through all of my word vomit and vague attempts at trying to understand what I'm doing.

 

I got new cables from infinite cables, and that wasn't the issue, still stuck at 1080p 8b 60hz

 

But I remembered that I had turned off dobly vision enhanced HDMI format when I first got it so I went in and changed that to standard and woot 4k is working.

 

Now I just have to figure out why the "enhanced format" seams to do the same thing it was doing previously, occasionally going black for a couple seconds.  This is because HDR isn't supported on "standard format".

[Psittac]

Looks like it was the GPU, I'm going to give it some time to see if it starts acting up but I went from an RTX3080 to an RTX2080s and it went straight to 4k hdr

 

guess I get to look for a new GPU

 

*edit: ok get this..... on the LG machine with the 3080.... it runs just fine on DP?  maybe it's my hdmi that's messing up?  I'm going to leave it as it is for a week and see if it starts acting up then swap it to HDMI and see if it messes up.  If it's the HDMI portion I'll use an adapter from DP to my sony and won't have to get a new GPU.  I don't understand any of this, none of it makes sense.  Why did it mess up on the LG before and not now?  The LG went crazy with nothing hooked to it?  This baffles me to no end

[Psittac]

*update*

So it was apparently something to do with the VRR, I've had that PC off for a few weeks, though my friend used it the night before last, but I turned it on just now and it acted up.  Even the OSD was going crazy but I was able to go through the menu and start tweaking things.... Turned off VRR and instantly fine.  This was on DP.

 

So my overall assumption is that HDMI on my 3080 has pooped out and the LG doesn't like VRR.  Those two combined quirks made life a living poop sandwich in trying to narrow it down.

 

Samsung is fine on 2080s HDMI and LG is fine on 3080 DP with VRR off.  I'm glad I didn't swap gpu's back yet cause I would have never known exactly what was going on.

 

*edit: I hate to mark my own answer as the solution, but for anyone down the road that looks this up, they won't have to read my incoherent rambling and cut to the chase.