Nvidia Ampere and LG OLED C9 issue

[VincentHanna]

Managed to get hold on an Nvidia 3070 whilst waiting for my 3090 to arrive.

I have LG OLED Firmware 05.00.10 and the latest Nvidia 460.79 driver

1) I no longer have the option of YCbCr422 under the Nvidia control panel 'change resolution' menu. I only have 420, 444 or RGB. What's going on there? I didn't have this issue with my 2080ti

2) I supposedly have a HDMI 2.1 cable connected directly from the GPU to the TV, and yet 60hz is the maximum refresh rate I can select. Surely it should now allow me to select 120hz?

Edit - I solved this issue by selecting from the 'PC' resolutions, instead of 'Ultra HD, HD, SD'

3) If I turn G-sync on there is a flicker on the screen unless I use YCbCr420

Are other people having these issues?

 

[VincentHanna]

Bump

 

[VincentHanna]

all fine here on 460.79 with 3090 + LG CX 48

Gsync is enabled 4K 120hz is active no flicker with full RGB and HDR on

what i have done & just worked
instant response (on) switches on auto with gsync anyway
turn game mode on as picture setting
tell port its PC in LG software
deep color on

no issues no flickers on hdmi - product code on the rain forest: B07WN8C7XV

make sure you have the latest firmware on the CX 3.11.30 fixed flickering in release notes

I have a LG C9 and RTX 3090 (though multiple RTX 3090s and 3080FEs and all bhavaiour similar) using same drivers and firmware on both TV and GPU.

First of all, I do have an odd quirk in that I get signal not displayed sometimes and a reboot solves issue, saw another thread with RTX 3090 and C9 combo so think may be handhake issue going on.

However once in Windows everything is fine. 120hz @ 4k, G-Sync, HDR 4:4:4 12bit / 12bit and eARC to Atmos all fine.

As others suggested, HDMI deep colour is the important one to enable. Enabling this will also enable instant game response anyways. For specific answers

1) I no longer have the option of YCbCr422 under the Nvidia control panel 'change resolution' menu. I only have 420, 444 or RGB. What's going on there? I didn't have this issue with my 2080ti

Amusingly I do not see YCbCr422 when running G-sync and 4K @ 120hz either. However this is a non-issue given you can see 444 which is the better option to pick all things being equal. Its what I have selected with mine at 12bit (I know LG C9 cannot display 12 bit, but recall vincent Teho's video where when you get option go 12 bit he believes)

3) If I turn G-sync on there is a flicker on the screen unless I use YCbCr420
No issue in that regards with RGB or 4:4:4, I suspect it may be your cable. My main HDMI 2.1 cable works perfect. I got a free one rated apparently rated at HDMI 2.1 more recently and that does flicker.

Smogsy suggested one, I use one with code: B08CS79VZN as I needed one with 5 meter length.

I would suggest changing HDMI cable in your shoes first. While I have not used a 3070, I have 3080 and 3090s and cannot imagine the 3070 with the same HDMI 2.1 port having any issues.

Thanks to you both

I searched Amazon for B07WN8C7XV as @smogsy suggested, and then selected the 3m version which is B083TZ2Y3Y. It arrived today and I just hooked it up

And yet the problem remains!

Deep Colour has been enabled on my C9 HDMI port since I got it.

The flicker only goes away if I turn G-sync off, but I want to use G-sync in Cyberpunk 2077.

 

[VincentHanna]

UPDATE

I swapped the HDMI port I was using on the LG C9 from HDMI 1 (Which was set to 'PC' under the HDMI options) to HDMI 4 (which my Xbox One X used to use, before I sold it) and there's no flicker now.

Yay

But also

?

 

[VincentHanna]

No, it was more like tiny glitching on the screen, rather than a black screen.

 

[VincentHanna]

New issue today - Anyone using eARC on the C9?

Installed an ASUS ROG Strix OC 3090 and set the output to 7.1 in Windows 10, then ran the sound test. All the sounds play, but they are only coming from either the left or right front speakers.

What the hell's going on now?

 

[VincentHanna]

No, should all work fine now. Mine does.

 

[VincentHanna]

Oh, do not see that. When going into windows see notification and usually when firing up a game for first time into fullscreen. Do not see message popping up ingame, that would wind me up if it did that. Yes this is with a C9 / latest update and 3090.

Same here, never in game.

@LukieBoy007
I use the console symbol on HDMI 4

It's worth trying different HDMI ports because my HDMI 1 had issues.

 

[VincentHanna]

I know that but i thought 4k 120hz was not possible with HDMI 2.0

It isn't.

Unless you force 8-bit color, limited RGB, and use 4:2:0 chroma subsampling and make sure HDR is off.

Then it might work but the image is compromised anyway.

 

[VincentHanna]

Yeah, it'll be mainly older games.

Doom Eternal just happens to run amazingly

Forza Horizon 4 is another that will run at pretty much extreme settings at 4k/120hz, as long as you keep the MSAA at 4x or lower.

 

[VincentHanna]

This issue still occurs

c9 on latest firmware and 3090 on latest drivers

Enabling Gsync at any resolution or any framerate results in raised gamma and flickering

Not on my C9.

Use a different HDMI port on the TV as that was my issue

 

[VincentHanna]

what cable and what settings in nvidia control panel? and do you have the tv in game console mode or PC mode?

This Cable:
https://www.amazon.co.uk/gp/product/B083TZ2Y3Y/

These settings:


I swapped out my 2080Ti for the 3090 and used the same HDMI port on the TV, which was HDMI 1 and it was set on the TV with the 'PC' symbol. This is where the issues came from (see earlier post in the thread) where I had flickering.

When I tried HDMI 4 which was set to 'Console' it worked fine with 4k/120hz/4:4:4/HDR on and G-sync enabled, with no issues at all.

 

[VincentHanna]

Because the TV is set to 'black level low' by default, which matches the limited output on the PC

If you set it to 'full', you just end up with raised blacks.