LG 48CX

Take a look of this video showcasing the 3080 along with a 48 CX (link takes you to 4:23 timestamp). Sorry for the noob question but what's the difference between setting the output color format to RGB vs 4:4:4 vs 4:2:2 in the NVIDA interface? Does RGB = 4:2:2? If so why present both options?

 
RGB is RGB and is the highest quality. It's a very noticeable difference for PC use with text.

But the problem is what the TV does when receiving that signal. Right now at anything higher than 60hz (with 4k) it's converting it to something like 422 (or somewhere between 422 and 444).
 
kalston said:
RGB is RGB and is the highest quality. It's a very noticeable difference for PC use with text.

But the problem is what the TV does when receiving that signal. Right now at anything higher than 60hz (with 4k) it's converting it to something like 422 (or somewhere between 422 and 444).
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Understood. For testing purposes how to you tell that the TV is converting / down sampling to the lower format? Just eyeball or is there a diagnostic mode on the TV to see what format its actually outputting?
 
As
domenic said:
Understood. For testing purposes how to you tell that the TV is converting / down sampling to the lower format? Just eyeball or is there a diagnostic mode on the TV to see what format its actually outputting?
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Monstieur said:
How? There is absolutely no mention of the downsampling.

Based on the appearance of the image, the GPU is indeed sending a true RGB signal. 4K 120 Hz RGB internally downsampled with PC icon looks identical to 4K 60 Hz RGB internally downsampled without PC icon. With PC icon, 4K 60 Hz RGB is not downsampled.
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Where do you view/change the colour settings in the NVIDIA control panel? For 4:4:4 or 4:2:2 etc?
 
domenic said:
Take a look of this video showcasing the 3080 along with a 48 CX (link takes you to 4:23 timestamp). Sorry for the noob question but what's the difference between setting the output color format to RGB vs 4:4:4 vs 4:2:2 in the NVIDA interface? Does RGB = 4:2:2? If so why present both options?

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Hmm, so he was able to select 120 Hz @ 10-bit with RGB. Interestingly, it looked like 12-bit and YCbCr444 were available in the drop-down boxes as well but he didn't try them. I suppose the only question is if the TV downsamples internally, and how noticeable that is. Personally, I don't care and am definitely in for a 3000 series card...I'm currently using 120 Hz with 4:2:0 and find it to be perfectly acceptable using it 8+ hours a day for work etc. but I would certainly welcome an improvement to small red text when I encounter it (error messages in PowerShell can be particularly difficult to read, but I only use PS occasionally).

lludson said:
Where do you view/change the colour settings in the NVIDIA control panel? For 4:4:4 or 4:2:2 etc?
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Open NVCP and on the left, it's in the "Change resolution" tab under the Display group.
 
Lateralus said:
Hmm, so he was able to select 120 Hz @ 10-bit with RGB. Interestingly, it looked like 12-bit and YCbCr444 were available in the drop-down boxes as well but he didn't try them. I suppose the only question is if the TV downsamples internally, and how noticeable that is. Personally, I don't care and am definitely in for a 3000 series card...I'm currently using 120 Hz with 4:2:0 and find it to be perfectly acceptable using it 8+ hours a day for work etc. but I would certainly welcome an improvement to small red text when I encounter it (error messages in PowerShell can be particularly difficult to read, but I only use PS occasionally).
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If it's a hardware limitation rather than something fixable via firmware then it would be a dealbreaker for me. Removing half of the chroma~color information is not acceptable.
Hoping it's fixed in a LG firmware update by november along with nvidia fixing the broken hdmi 2.1 VRR with driver update(s).

elvn said:
RGB is 444. YCbCr 444 just has to be converted to RGB.
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https://www.reddit.com/r/hardware/comments/8rlf2z/psa_4k_144_hz_monitors_use_chroma_subsampling_for/
Since RGB-format images don't have luma or chroma components, you can't have "chroma subsampling" on an RGB image, since there are no chroma values for you to subsample in the first place. Terms like "RGB 4:4:4" are redundant/nonsensical. RGB format is always full resolution in all channels, which is equivalent or better than YCbCr 4:4:4. You can just call it RGB, RGB is always "4:4:4".
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Also, chroma subsampling is not a form of compression, because it doesn't involve any de-compression on the receiving side to recover any of the data. It is simply gone. 4:2:2 removes half the color information from the image, and 4:2:0 removes 3/4 of it, and you don't get any of it back. The information is simply removed, and that's all there is to it. So please don't refer to it as "4:2:2 compression" or "compressed using chroma subsampling" or things like that, it's no more a form of compression than simply reducing resolution from 4K to 1080p is; that isn't compression, that's just reducing the resolution. By the same token, 4:2:2 isn't compression, it's just subsampling (reducing the resolution on 2/3 of the components).
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lludson said:
Where do you view/change the colour settings in the NVIDIA control panel? For 4:4:4 or 4:2:2 etc?
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Just to reiterate, what people are saying is that even when you send a RGB signal (4:4:4) to the TV with the drivers reporting it being sent, the CX OLED TVs at 120Hz 4k on hdmi 2.1 are internally downsampling to lower chroma which looks just like the non-pc icon input mode of the TV at 60hz (which doesn't accept and show RGB).
 
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@Lateralus - thank you.


I am having a hell of a time getting these 3 CX's to all work on my Titan Pascal XP SLI rig, using the NvidiaCP.

Center screen on HDMI does 4k in the "PC" Section at 120hz - NO HDR
Left and Right on HDMI/Club 3D adapter do 4k in the "ULTRA HD" section at 60hz. - Both run in HDR

My screens go black if I try to set the left and right on HDMI/DP @120hz in the PC section of resolutions.

I unplugged one and get a really corrupt looking screen (tried it on the right one).

I just don't know what the hell to do. And these PASCAL TITAN XP's are 4 years old. I have no idea if I am struggling because of that. And if the 3090 I want to move to will let me do this alright. I am using great cables...

To have my three screens as below totally sucks ass.

4k 60hz HDR || 4k 120hz no HDR || 4k 60hz HDR


EDIT: Whelp.
- I can do all 1080p 120hz HDR.
- All at 4k 120hz is not yet possible for me and my Pascal Titan XP's....
 
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Great news to hear that broken VRR is just an nvidia driver thing that will probably be fixed with a hotfix driver. As for the whole 422 downsampling thing, eh I never even use my CX for desktop use so it's been sitting at 120Hz 420 on my 2080 Ti since July 1st so that doesn't bother me. I just want to finally be able to play at 4k120Hz VRR with HDR on.
 
I will tell all of you guys straight up, at least with the C9 and the RTX 3080, there has to be a few very serious bugs with the display driver, Windows 10, and or the LG and or firmware that will have to be patched. Either one or all of them, I have no clue where to start.

It's so annoying I'm seriously considering pulling my new RTX 3080 video card for now. Actually, I probably will unless I can find a fix online somewhere.

The "Instant Game Response is Launched" message is constantly popping up at random several times a minute which blacks out the screen for a good second. Super annoying. I am also exciting games only to be greeted with a distorted glitched out 4K desktop that I cannot recover from OR the game launches to a black screen that I cannot recover from.

I'm into day 2 since buying the RTX 3080 and I've been forced to reset / reboot my PC at least 15+ times

Can someone please tell me if there is a method to FORCE "instant Game Response" to just stay the FUCK on, I don't need it switched on or off automatically, I don't need a god damn notification message in the corner of my screen each and every single time. No reason that I can't just go into my settings and see if this feature is on or off. Also, where is the dark theme for the LG menu system? I thought GUI people were a specialized position within these teams that design, develop and build these TV's. Seriosuly dropping the ball here.
 
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I have the 77", not the 48", but it's the same TV model so I'm gonna post here. Anyways I'm pretty annoyed that these TV's only support G-Sync with 16xx and 20xx cards, because I'm under the impression it's an artificial limitation. I have been enjoying 4k 120z with lesser color chroma and it's actually been pretty sweet, but I would love me some G-Sync as I can still see screen tearing on everything. I suppose it's my fault for not reading the fine print on the product page for the TV, but since I've already used various G-Sync monitors with these card, I wouldn't intuitively think that I wouldn't be able to use G-Sync without the newest cards.
 
From AVS Forum thread:
https://www.avsforum.com/threads/2020-lg-cx–gx-dedicated-gaming-thread-consoles-and-pc.3138274/post-60111929


laxu said:
It doesn’t seem to be a bandwidth issue because it happens at 8-bit color as well and 1080p 120 Hz.
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André Fagundes said:
Just tested with 1080p and happened as you said, only 59 and 60hz displayed 4:4:4 but for 120hz, 100hz and even lower refresh rates like 50hz and 30hz were displayed at 4:2:2. Damn. Is there a link were we could report this and LG actually listen to it? If someone like Linus Tech Tips did a video criticizing this issue I bet LG would get this fixed in a week.
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I bought mine last week and have 30 days to return to microcenter. Downsampling to 4:2:2 chroma is unacceptable for pc use so if it’s not fixed quickly I’ll have no choice but to return it. Luckily still have my monitor awaiting sale.

Edit: just saw it’s a known bug here for months. Packed up and will be returning. I’m not really happy with the size and extreme glossiness anyway for PC desktop usage. I’ll grab a 65” CX for my TV area instead.
 
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I posted this over on AVS - https://www.avsforum.com/threads/20...consoles-and-pc.3138274/page-74#post-60111929

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As mentioned above we need to get some publicity to put a spotlight on the 4:4:4 at 120Hz issue to make LG aware of it and put pressure on them to correct it. This TV & video card isn't a random combination - rather its seems to be a marketing partnership between LG & NVIDA based on the fact its the only TV line GSYNC certified and had a product placement in the 30 series kickoff presentation. The last thing either company want is this tarnished.

We need to figure out how to get word to some of the YouTubers out there that are already doing videos with the LG CX series and the ones that frequently cover these kind of topics / issues already.

Two such channels (below) are Stop the FOMO (48K subs) and HDTVTest (217K subs). Recently both have covered the LG CX & C9 TVs and their integration with the upcoming new consoles and 30 series NVIDIA cards discussing the 40 vs 48 Gbps bandwidth controversy. If we could somehow get word of this to them I bet they would either do a video just on it or cover the topic in one of their other videos since both have said they are eagerly awaiting 30 series cards in order to specifically put the LG OLEDs through their paces. FOMO has already declared the LG CX OLED the best gaming TV currently in a couple of his videos. They also seem to have communication channels to many of the TV manufacturers since when they find discrepancies or issues with products they sometimes seem to get statements or clarifications afterwards.

So how do we get word to these guys or similar outlets so they can be our megaphone to raise awareness and hopefully put pressure on LG to correct quickly?

https://www.youtube.com/channel/UCqHuvvETx7PKapuchT2BnSA
https://www.youtube.com/channel/UCcCYOO2uYPnG-21WDOWdwew
 
I wonder if anyone has mentioned/asked in the rtings comments section of the 'CX as a monitor' review? They are pretty thorough and used to be good about responding to questions. They're probably established enough by now that they might have a more direct way to raise questions and concerns directly with LG also.

I might look later; surely this has come up by now...

Edit: Looks like someone did ask about it in general terms and they do plan on retesting once they have an HDMI 2.1 source. They probably weren't able to secure a 3080 either, so it might be a while. Hopefully their testing is very thorough when they revisit it.
 
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Was bored, so I decided to play some Battlefield 4 @ 4K, max settings.

HOLY BEJEBUS!!! I had forgotten how much fun this game was. Not only that, but it still has a massive player base. Also... it looks gorgeous on this display (as does pretty much every game). Plays like a dream, too.

Where's my freakin 3080?!?!?! Nvidia... lets go!!!!
 
So basically, putting aside some of the other known issues, the two big ones at the moment:

1: Black screen when VRR is enabled; affects C9 and CX [Likely NVIDIA driver bug?]

2: 120Hz resolutions being downsampled to 4:2:2; 60Hz resolutions display 4:4:4 as expected; affect CX, works on C9.

The first will get fixed by NVIDIA shortly. The second is likely a firmware bug given the C9 works as expected; its just a matter of brining it to LGs attention.
 
gamerk2 said:
So basically, putting aside some of the other known issues, the two big ones at the moment:

1: Black screen when VRR is enabled; affects C9 and CX [Likely NVIDIA driver bug?]

2: 120Hz resolutions being downsampled to 4:2:2; 60Hz resolutions display 4:4:4 as expected; affect CX, works on C9.

The first will get fixed by NVIDIA shortly. The second is likely a firmware bug given the C9 works as expected; its just a matter of brining it to LGs attention.
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Yes! Now we just need to figure out how to get this to LG & NVIDIA's attention ASAP as I mentioned above.
 
madpistol said:
Was bored, so I decided to play some Battlefield 4 @ 4K, max settings.
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Yeah, I've gotten back into BF4 since picking up my 55CX. I do 1440p all settings maxed, with nVidia sharpening and 200% resolution scale. It's basically pegged at 119FPS, looks like 4k, runs like silk. It's fun as hell operating all the big ass vehicles on this big ass screen. Flying around in choppers and jets is fucking bliss. Makes me want to get into flight sims, it seems so realistic!
 
1440p with 200% scale? Why not just play at 4k then? Since you seemingly have the horsepower for 5k.
 
kalston said:
1440p with 200% scale? Why not just play at 4k then? Since you seemingly have the horsepower for 5k.
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Settings were carried over from the last time I had played, on a 1440p monitor. I did try 4k but things seemed more responsive at 1440. Perhaps reading about higher input lag @ 4k gave me some placebo effect. TBH it didn't look much different (to my eyes).
 
NukeDukem said:
Yeah, I've gotten back into BF4 since picking up my 55CX. I do 1440p all settings maxed, with nVidia sharpening and 200% resolution scale. It's basically pegged at 119FPS, looks like 4k, runs like silk. It's fun as hell operating all the big ass vehicles on this big ass screen. Flying around in choppers and jets is fucking bliss. Makes me want to get into flight sims, it seems so realistic!
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Great. Where do you find the settings for 200% scaling and shaprening?
 
Hopefully 422 is firmware-eable :cautious:. .....

And they get it straightened out by november :rolleyes:
 
elvn said:
Hopefully 422 is firmware-eable :cautious:. .....

And they get it straightened out by november :rolleyes:
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Lol given that they have known about other issues like raised blacks with Dolby Vision and have yet to do anything about it, once they do find about the 422 chroma reduction, I wouldn't be surprised if it takes them a year to fix it.
 
Darn it. I should have waited before buying three of these. For multi monitor gaming.

I have spent $5000 on something I didn't know would work well enough...or at least yet.

Ugh.
 
TBH I'm getting pretty sick of using this thing as a monitor. Really wish something comparable was available in 40" size.

Hopefully once I get a 3080/3090 and Nvidia/LG fix this 4K/120hz issue it will rejuvenate my enjoyment.
 
really want this to work out, OLED is so beautiful dont want to go back to a IPS or VA. that Alienware is rather expensive. I heard late 2021 2020 is where Oled below 48 inches will start coming to monitors. thats a long time to wait.
 
lludson said:
Darn it. I should have waited before buying three of these. For multi monitor gaming.

I have spent $5000 on something I didn't know would work well enough...or at least yet.

Ugh.
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I still dont get why you would buy 3 of these instead of a kickass VR setup. Seems like a no brainer for Sim pits, where you can look around and really feel like you are in the game :)
 
lludson said:
Darn it. I should have waited before buying three of these. For multi monitor gaming.

I have spent $5000 on something I didn't know would work well enough...or at least yet.

Ugh.
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Other than your issues getting all of them to 4K 120 Hz, you will not notice a difference between 4:4:4 and 4:2:2 in gaming.
 
Pr0Pain said:
I still dont get why you would buy 3 of these instead of a kickass VR setup. Seems like a no brainer for Sim pits, where you can look around and really feel like you are in the game :)
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Well, I just can't handle not being able to see my controls. I have a $3,500 F1 wheel coming that has a ton of controls on it. I don't like not being able to see around the room in general either. A Track IR works just fine for me for looking around in sims if I want the head motion. But right now these babies give me 180 degrees of view. That is fantastic.

kasakka - Yeah. I just hope I can eventually get the 3 @ 4k 120 hz - preferably in HDR, which also doesn't seem possible right now. I hope getting another Club 3d adapter and going all display port will help me with this, along with a fix from LG. Maybe I have to start with them at @60hz for a while. Certainly this must be fixable through firmware? They have to do it. They've advertised this display as being that capable, touting the features. And maybe the move from my old Pascal Titan XP's to a 3090 will help. I have no idea.

@MistaSparkful - I was thinking about returns. I didn't get them locally though. I have 3 similar sized 1080p TV's in the house which are really in need of an upgrade anyway. They are all 10 years old+.

UPDATE:
- I have all 3 screens running at 1440p @120 w/HDR.

- 2 are at 10bpc, RGB, Full DR

- The one on HDMI is at 8bpc, RGB, Full DR
 
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lludson said:
kasakka - Yeah. I just hope I can eventually get the 3 @ 4k 120 hz - preferably in HDR, which also doesn't seem possible right now. I hope getting another Club 3d adapter and going all display port will help me with this, along with a fix from LG. Maybe I have to start with them at @60hz for a while. Certainly this must be fixable through firmware? They have to do it. They've advertised this display as being that capable, touting the features. And maybe the move from my old Pascal Titan XP's to a 3090 will help. I have no idea.
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Have you tried if they work at say 1080p or 1440p 120 Hz together? I think your use case is a very specific niche thing. The Pascal Titan XPs are most likely part of the problem, I don't know if they even support DP 1.4 and they definitely don't support it with DSC so the Club3D adapter might not help.
 
kasakka said:
Have you tried if they work at say 1080p or 1440p 120 Hz together? I think your use case is a very specific niche thing. The Pascal Titan XPs are most likely part of the problem, I don't know if they even support DP 1.4 and they definitely don't support it with DSC so the Club3D adapter might not help.
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kasakka - yes they do work at 1440p, 120hz + HDR. I had just updated my last post. I am running into trouble when I then try to change a DP monitor to 4k 120hz. All my screens go black. And I have to unplug the DP monitors. Sigh.
 
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