Can't get 4K 120Hz LG OLED C1

[Keltyx98]

Hello, I just got my DP - HDMI 2.1 adapter but I can't get 4k 120Hz in the Nvidia control panel. The "PC" resolutions only get to 2560x1440 120Hz.

It's strange because when I initially connected everything it was working, but the borders were cropped. I solved the borders problem, disconnected-reconnected a few times and now I can't find the 4k 120Hz resolution.

Already restarted the PC, updated drivers, checked windows refresh rate, reconnected cable + adapter in various ways and .

Adapter and cable shouldn't be a problem since I already managed to get 4k 120Hz, they are both hdmi 2.1 rated. 

[Keltyx98]

So maybe I found the issue.

I connected my GTX 1070 directly with HDMI and I could select 4k 120Hz without HDR. If I connect it via DP + adapter I don't have 4k 120Hz but I get HDR.

Reading on the box of the adapter it says "This product is specifically designed to work with the latest GPU's which supports DSC1.2" .

Could that be the reason? It's strange because I'm pretty sure it worked 2h ago

[Alex Atkin UK]

35 minutes ago, Keltyx98 said:

I connected my GTX 1070 directly with HDMI and I could select 4k 120Hz without HDR.

That's a bit odd in itself, as far as I know the GTX 1070 cannot do 4K 120Hz over ANY output, period.

 

Its why I ended up with a GTX 1650 JUST to get my desktop to work at 4K 120Hz at all.

[Stahlmann]

The adapter might not support the required bandwidth. You could try to create a custom resolution.

[Glenwing]

21 hours ago, Alex Atkin UK said:

That's a bit odd in itself, as far as I know the GTX 1070 cannot do 4K 120Hz over ANY output, period.

 

Its why I ended up with a GTX 1650 JUST to get my desktop to work at 4K 120Hz at all.

GTX 1070 can support up to 4K 120 Hz with DisplayPort. It can also support it over HDMI if 4:2:0 chroma subsampling is used.

[Keltyx98]

20 hours ago, Stahlmann said:

You could try to create a custom resolution

Thanks! Creating a custom resolution worked! 
Now I have 4k 120Hz WITH HDR 

[LG C2]

I've also tried creating a custom resolution but it didn't work for me. When I apply the custom resolution, the screen flashes, and it goes back to 60hz. Any ideas?

[BuzzingBee]

15 hours ago, LG C2 said:

I've also tried creating a custom resolution but it didn't work for me. When I apply the custom resolution, the screen flashes, and it goes back to 60hz. Any ideas?

What's your GPU? If you have older GPU like 1000-2000 series you may get 4k 120Hz if display is set at 8-bit 4:2:0. You also need to check if your TV is on PC mode and HDMI ultra HD deep colour turned on. 

[e22big]

On 1/26/2023 at 10:52 AM, LG C2 said:

I've also tried creating a custom resolution but it didn't work for me. When I apply the custom resolution, the screen flashes, and it goes back to 60hz. Any ideas?

If custom resolution doesn't work then your hardware is probably inadequate - either the port or the cable. If you have DisplayPort then maybe changing the adapter will help (or if you have HDMI 2.1, then just find a new cable)

[LG C2]

I have a 2070 Ti Max Q. I used the LG CX @4K 120hz for a year. So I know my gpu is capable of doing it. When I upgraded to the C2, it stopped working. I’ve tried everything and the resolution simply doesn’t show up under the PC options in the nvidia panel.