Question Do i have HDMI 2.1 issues?

Mar 4, 2021
Hey you guys... Ive bought a new TV its the LG OLED55B19LA, it supports Nvidia gsync, and up to 120 HZ.
So i connected it to my PC with a 3090 with a (i have to admit rather cheap) 5M HDMI 2.1 cable. Its the second monitor so to speak so i can use the PC like a console (Pc is near the livin room). There were 2 inputs that showed support for 120Hz so i choose one of these.

Before i had an older 1080P TV connected to the same PC. No issues there.

@ first i thought everything was fine. I could get 120 HZ (via windows options) and gsync was enabled by default. I turned vsync to off in all my games and i everything seems to work just the way it should be.

But then the wonkyness kicked in. When i used dlss in Control i noticed some glitches. Like the Picture or a part of it would warp away for a split second, So i disabled DLSS and everything went back to normal.
Oh and there was a error message once on my desktop stating a C++ crash or something.

Then i tested Watch dogs legion. Everything worked good even with dlss and HDR. The only odd thing was that when ever i changed the resolution or dlss options ubisoft connect would crash and the game would quit itself. Also there was a weird aliasing effect that created white flickering around some specific edges.. but very few.

And now ive played Assasins creed odyssey.. a rather long playsession for about 1 hour and 20 Minutes. While this game never showed any weird behavior before at the end of the playsession i had a blackscreen for a split second (sailing with a ship) and at some points a similiar splitsecond warping of the image.

So while everything was fine before i switched TV's and the cable its most likely that my issues are related to the new setup.

I even switched off gsync. But it seems not to have been the problem.

Do you guys have any ideas?


DLSS can lead to artifacting, basically predicting what something should look like. When it was brand new there were tons of posts about flickering images and other symptoms.

Considering you went from 1080p to 4K, that is going to be a huge jump in load on the GPU. Monitor memory temperatures as that is a common issue with RTX3090, the memory on the back of the card may be getting too warm. You might try pointing a fan at the back of the card. Also have the whole POSCAP issue, where there may be some instability running high frequencies, you can try downclocking the card a little. GDDR6X is ECC memory, so those blank spots could just be it recovering and carrying on.
Mar 4, 2021
Hey Eximo and thank you very much for your reply and yur suggestions!

Actually i dont think its the GPU or the VRAM overheating.

First i have a custom model the Gainward Phoenix (non oc base model).
And i actually cant monitor the Vram-temps right now.. as afterburner wont let me choose this specific option. And i also have a 1440P 144Hz gsync compatible PC monitor besides my tv.

I had longer playsessions in these games with similiar settings before and i could play for hours without any artifacting or this weird warping issue that ive got with Control (using dlss to upscale from 1080P to 4k) and my longer playsession in AC Odyssey. I mostly capped my frames to 60 FPS when these issues happened wether using ingame settings or through Nvidia CP. So it should be basically the same or at least a similiar load on the GPU as before. Just with 100 HZ and gsync and fps capped to 60 instead of 60HZ and Vsync.

So what similiar settings you will ask... i often used dsr to emulate 1440P on the 1080P TV. Also any game with raytracing would push the GPU very hard. Especially Control with all raytracing glory in 1080P or Cyberpunk with ultra settings in 1440P with dlss set to quality will let the GPU sound like its goin to take off.

I easily reach 78 and sometimes even 80 degrees peak for the GPU but i didnt see any issues. And now (in ac odyssey) the weird stuff happened @ a range between 72-75 degrees.

Ive just finished a one hour playsession of Metro Exodus remastered (also capped to 60 FPS using vsync) on my regular monitor (AOC)on ultra settings, 1440P ,dlss quality-mode and had no issues.

Could this rather be a cable bandwith problem? I have read that only HDMI certified cables with not more than 3 meters in lenght can guerantee the full throughput. Or at least ´people reporting that they had issues with a bunch of not really certified cables that were more than 3 Meters in lenght.

Also the Control issue happened in a very early state (so rather cool gpu) with not much goin on @ the screen (searching empty rooms) and the glitching of the screen was pretty noticeable (and it went away when dlss was set to off). While in AC odyssey it came after a rather long playtime and even with a short blackout of the screen. And maybe even some audio cuts (but im not really sure of that).

But it seems weird to me that the problem in AC odyssey took rather long to show itself.

Anyway ive ordered a 3 Meter and hdmi verified 2.1 cable and will continue testing.
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Mar 4, 2021
Other tools should let you monitor memory temps on the GPU. Try hwinfo64.

Yes, it could very well be the cable throwing errors.
Hey Eximo i just recreated the issue in Ac odyssey. This time the warping image came withnin 10 minutes and i definately had a sound cutout for a bief second. And i also got an c++ runtime error again when i exited the game.

I revcorded the temps via GPUZ:

Max GPU Temp was 76,7 degrees celsuis
Max Vram Temp was 86,0 degrees
The "hot spot" (whatever that value means) was 87,3 degrees.

For what ive read so far this isnt half bad for a 3090.

Others on the net easily hit 92 degress while gaming and some even over 100 degrees in mining situations.

So im thinking its really not a heat related issue or what do you think?

Update: Just out of curiosity i wanted to check what temps i get when i use my second monitor running @ 120Hz and using uncapped fps with gsync.

15 Minute Playsession Cyberpunk on ultra with rt, 1440P dlss quality-mode and these are the max-temps:.

GPU Temp: 80 degrees
Hot Spot: 91
Vram: 94

So right on the edge of the typical recommended operating temperature of 95C for gddr6.

But there were no such issues as on the oled.
So im now really confident to say my problems there arent heat related.

And i will never use the card with uncapped fps again as im afraid of these Vram temps XD
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