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From reviewing the RTINGS article:

Ouch, looks like LG messed up the 120 hz BFI.

And the 4K/120 input lag is higher, and the VRR input lag quite a bit higher yet... :(

Looks like I will be sticking with my 38LG for the foreseeable future.
 

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It's weird, wasn't input lag said to be generally lower at 120Hz? In any case, I don't find it "brutally unplayable".
 

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the CX rtings review says :
I posted in the owners' thread that this isn't the case for my 77" CX—I can set the TV to 120Hz/1080p/4:4:4, running the latest firmware.

Edit: it turns out that this is only the case when HDR is activated in Windows. Full chroma is not supported in SDR at [email protected]

I'd like to get to the bottom to this question of whether PC mode is necessary for 4:4:4 on the CX. Maybe I'm missing something, but it seems to be working for me with the input icon set to "game console" (I renamed it to Windows) in HDR game mode. Take a look at the attached pic and see what you think. On the other hand, I cannot see any evidence of extra banding in HDR game mode when the input is switched to "PC" (icon and name).

In short, it seems not to matter whether the input is set to "game console" or "PC," whereas it definitely did matter on my C7 (PC mode was unusable for HDR). Could this be a change on the 2020 models? Are there specific test images that would reveal any subtle differences?
 

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A user over on [H] got the 48CX. The disappointing news is that with current GPUs (HDMI 2.0b), you can in fact do 4K/120Hz at 4:2:0, BUT it disables HDR AND G-Sync. Only way to get either/or HDR and G-Sync to work again is to drop down to 2560x1440/120 Hz.

So looks like I'm not buying 48CX until Ampere releases... :mad:



That is normal.. u need a HDMI 2.1 vídeo Card for the rest stuff
For lower resolution no problem
Not a tv problem
Is the source the "problem"
 

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Wait.... how does VRR introduce more input lag?


I thought the whole point of technologies like g-sync was to reduce input lag even further. This makes no sense
 

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think you need to use the 4K res test image
FWIW, the pink/purple image was scaled at 100% in Paint. I tried the quick brown fox 4k image too and still couldn't see much if any difference.

Then I realized that maybe running Windows in HDR had something to do with it. Sure enough, the differences are still obvious in SDR. Why would HDR affect chroma subsampling? On the plus side, the quick brown fox image still looks pretty good even at 4:2:2 in HDR.
 

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Wait.... how does VRR introduce more input lag?


I thought the whole point of technologies like g-sync was to reduce input lag even further. This makes no sense

VRR should in theory be significantly reducing input lag, for sub-120fps gaming

120 fps w/ VSYNC off on a 123 Hz display, should have the exact same input lag as 120 fps w/ GSYNC on a 123 Hz display. Although the former would have tearing.

but if you are playing a 30 fps console game, the input lag will be significantly reduced as the display (ideally) refreshes in 1/120=8.3ms rather than 1/30=33.3ms. And you don't have to worry about the additional frame of input lag caused by vsync. People are measuring input lag from the middle of the tv before the frame readout is complete which is why input lag is reported as sub-8.3ms times for 1080/[email protected] Note that it still takes much longer though for the console to render a 30fps frame, so the display is only half of the equation for lowering input lag while gaming, the other is increasing your fps.

Reduced input lag is probably about half the importance of gsync, the other being tear-free gaming. So yeah it is a pretty big blunder if vrr/gsync is significantly increasing input lag.

There is really no reason to be using vrr for gaming if it is causing input lag. Might as well just use vsync which is less glitchy if you want tear-free gaming at the cost of higher input lag.
 

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From reviewing the RTINGS article:

Ouch, looks like LG messed up the 120 hz BFI.

And the 4K/120 input lag is higher, and the VRR input lag quite a bit higher yet... :(

Looks like I will be sticking with my 38LG for the foreseeable future.

The 4k lag is exaggerated under different conditions



The 120hz BFI works in game mode only for me - on all content.. Otherwise same crap as RTINGS.
 

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The 4k lag is exaggerated under different conditions



The 120hz BFI works in game mode only for me - on all content.. Otherwise same crap as RTINGS.

That's good new then. I hope someone tests the input lag at 4k120 HDR 10-bit 4:4:4 PC Game Mode with 50% BFI when hdmi 2.1 gpus are out. I'd rather run it like that then with Gsync anyways. Hopefully it works well with those settings which I would consider to be the ultimate settings for this display. I'd just leave the tv at those settings for everything PC usage (gaming, watching movies, browsing the web)
 

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The 4k lag is exaggerated under different conditions



The 120hz BFI works in game mode only for me - on all content.. Otherwise same crap as RTINGS.
You saying RTINGS tested the 120 Hz BFI outside of game mode? Why on Earth would they do that... You are saying 120 Hz BFI is super clear in Game Mode?

VRR also breaking more stuff?:

 

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I'd like to get to the bottom to this question of whether PC mode is necessary for 4:4:4 on the CX. Maybe I'm missing something, but it seems to be working for me with the input icon set to "game console" (I renamed it to Windows) in HDR game mode.
Vincent stated the same already with C9 but reviewers are not that carefully testing things or they just don't care :) (see below)

For example Kuro RHINO's comment that he never got a reply to:
"I sincerely thank you for this great analysis Vincent, on behalf of us TV gamers. The results are quite interesting, especially as a gamer myself on the C9. However, I discovered some additional Game mode quirks on the C9 and it would be greatly appreciated if you could have a look:
- Dithering near black seems to be disabled in Game mode, slightly increasing video noise in very dark scenes
- Upscaling appears worse in Game mode, noticed especially on game consoles outputting at 1080p or less (e.g. PS3)
- Lastly, in Game mode, a very strange elliptical pattern seems to appear on very dark full field slides (around or less than 5% grey), thankfully this is not noticed in normal material"


Can you test these first?

On the other hand, I cannot see any evidence of extra banding in HDR game mode when the input is switched to "PC" (icon and name).

In short, it seems not to matter whether the input is set to "game console" or "PC," whereas it definitely did matter on my C7 (PC mode was unusable for HDR). Could this be a change on the 2020 models? Are there specific test images that would reveal any subtle differences?
I can give you video samples later, but first take a look at "Chroma 4:4:4" and "Banding" part of section I. of this post:
- as it turned out, LG didn't provide proper chroma 4:4:4!
- all the used samples are linked there so you can download them and try them out

Test setup:
- PC: set 24 Hz for the dislpay, RGB full, 12 bit (nvidia doesn't allow us to set 10bit for whatever reason :( )
- TV:
-- black level: High
-- SDR: ISF Dark room (gamma 2.4, warm2, oled light 33, rest is at default/disabled)
-- SDR: Game mode (gamma 2.4, warm2, oled light 33, rest is at default/disabled)
-- HDR10: Cinema (all options at default/disabled)
-- DoVi: Cinema (all options at default/disabled)

It would be nice to try these out on both C7 and CX if you still have the C7.

The biggest issue with PC mode on C8/C9 is:
- banding/posterisation especially with HDR10 content (but it can be visible with SDR as well), mostly in dark content

Lastly, the HTPC community would be really greatful for you for testing these (since noone was willing to do it so far)!

Thanks, and we can continue from here later.
 

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VRR should in theory be significantly reducing input lag, for sub-120fps gaming

120 fps w/ VSYNC off on a 123 Hz display, should have the exact same input lag as 120 fps w/ GSYNC on a 123 Hz display. Although the former would have tearing.

but if you are playing a 30 fps console game, the input lag will be significantly reduced as the display (ideally) refreshes in 1/120=8.3ms rather than 1/30=33.3ms. And you don't have to worry about the additional frame of input lag caused by vsync. People are measuring input lag from the middle of the tv before the frame readout is complete which is why input lag is reported as sub-8.3ms times for 1080/[email protected] Note that it still takes much longer though for the console to render a 30fps frame, so the display is only half of the equation for lowering input lag while gaming, the other is increasing your fps.

Reduced input lag is probably about half the importance of gsync, the other being tear-free gaming. So yeah it is a pretty big blunder if vrr/gsync is significantly increasing input lag.

There is really no reason to be using vrr for gaming if it is causing input lag. Might as well just use vsync which is less glitchy if you want tear-free gaming at the cost of higher input lag.

This is why I find it so strange, I would hope that maybe they were using an older firmware or this is part of a firmware bug.


VRR should not be introducing input lag, it should be reducing it.
 

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Hi there i'm intending to get the CX but I'm torn between the 48" & 55", I will place it in my room & only use it as a Gaming TV I'm not a PC gamer I do my computer work on my laptop so won't use it as monitor. I'll place it on a TV stand & sit 3-4 feet away, can advise on which size I should go for? Thank you.
 

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I'm thinking of purchasing a CX in November, hopefully these issues are fixed by then. I'm really want to get a good OLED for movie watching and gaming but it seems like every OLED has one issue or another. I may just have to wait another year or two until these issues are resolved.
 
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