LG 48CX

Monstieur

Limp Gawd
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Jun 10, 2011
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432
Nope. Definitely see some stuttering around 100-120 FPS. My test case is Battlefield 1.

Does anyone know a fix for this? The display seems fine from what I can tell, so I dunno.
Unchecking the Enable settings for the selected display model checkbox fixes this. You can test for stuttering by looking at the Hz value in the FreeSync Information screen on the CX when running at a constant framerate capped below 120 fps. If the Hz value changes while the frame rate is constant, G-SYNC is stuttering.
 

Monstieur

Limp Gawd
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Jun 10, 2011
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432
What about with HDR? Looking for someone to confirm this is working properly with all of the main settings HDR, GSYNC, 4:4:4, 10-Bit, 120hz
It works fine. That's what I use globally on the desktop and in all games. The G-SYNC stuttering fix is posted above.
 

Kev13Dd

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Apr 16, 2013
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Does setting ClearType to greyscale, or straight-up disabling ClearType altogether, not aleliviate the issue? (this can be easily achieved via Better ClearType Tuner)

Or is that exactly what the issue is - that you're not used to using text that is rendered without sub-pixel anti-aliasing?
I had to settle for greyscale, because Cleartype just added too much fringe to the edges that really stood out at times. Some apps/colors/fonts are fine, but you'll occasionally get a combo that Cleartype butchers



Certain text on certain colors just adds super strange fringe. Like the green edge on that white text. It stands out from a mile away and really catches your eye as off. Cleartype has been designed and honed on the RGB pixel arrangement, and the RGBW and slightly different sized sub-pixels will stand out in certain edge cases that Cleartype never could have anticipated

And greyscale isn't perfect either—because I'm not used to a greyscale edge on text, text looks like it has a slight shadow, like it's been over sharpened. Makes my eyes feel like they aren't focused. Again this stands out most on certain colors combos



That soft white shadow on the edge of the 4 and inside the 0? My brain can't not see it. I'm not sitting close enough to see individual pixels, but the panel is so sharp—and this subpixel not being normal—that text is just always going to be an issue personally. In Windows at least
 

Groto

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It works fine. That's what I use globally on the desktop and in all games. The G-SYNC stuttering fix is posted above.
So with the workaround all of these together work properly at the same time: HDR, GSYNC, 4:4:4, 10-Bit, 120hz? So no more compromises with this screen and latest firmware? Just trying to be clear.
 

madpistol

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Unchecking the Enable settings for the selected display model checkbox fixes this. You can test for stuttering by looking at the Hz value in the FreeSync Information screen on the CX when running at a constant framerate capped below 120 fps. If the Hz value changes while the frame rate is constant, G-SYNC is stuttering.

Unfortunately, this doesn't work. It says VRR, but the refresh is static. You can tell because there is tearing when running Heaven 4.0 around 70-80 FPS.
 

gordy

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Certain text on certain colors just adds super strange fringe. Like the green edge on that white text. It stands out from a mile away and really catches your eye as off. Cleartype has been designed and honed on the RGB pixel arrangement, and the RGBW and slightly different sized sub-pixels will stand out in certain edge cases that Cleartype never could have anticipated
having spent some time tuning cleartype on this screen - I think you have your contrast too high if you can see that green edge. I know when a white edge splits a pixel you get full red + full green + no blue and it looks just like that even on an LCD. I repro'd it on my screen and took this picture - the green edge is clearly visible in the photo but I cannot see it unless I place my nose about 6" from the screen - and from that close it looks no different than an LCD:
20201019_151036.jpg


..the only edge that sticks out and is definitely not present on an LCD is the the red edge on the left side of the yellow block - though I've lowered my contrast to the point where I can't even see that from an arm's length away (I'm using contrast 50, brightness 50, oled 75, and everything else 0, warm 1 white balance, and the gpu is all zeros w/temp at 6500K)
 

elvn

Supreme [H]ardness
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May 5, 2006
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Unfortunately, this doesn't work. It says VRR, but the refresh is static. You can tell because there is tearing when running Heaven 4.0 around 70-80 FPS.
Well, if he's disabling display specific VRR settings for the display it could fix the stuttering but yeah, you'd think it would disable VRR for that display which means tearing or reverting to regular v-sync (or fast sync) if either of those was still enabled.

He's talking about this panel.


aid_4768_compatible.png

I am all for a working fix but it seems like there are varied reports at the moment with a lot of people still having stuttering issues with VRR.
 

steiNetti

Weaksauce
Joined
Sep 23, 2020
Messages
82
Unfortunately, this doesn't work. It says VRR, but the refresh is static. You can tell because there is tearing when running Heaven 4.0 around 70-80 FPS.
Powercycle the TV and disabling G-Sync, apply, reenable G-Sync.

I have the same (or at least a similar) issue with my 2070S on HDMI 2.0 on both the .20 and .25 firmwares and also had similar issues on my old Momentum 43" FreeSync.

I think that weird stuff is either caused by Windows 10 or the nvidia drivers.. sometimes I even have to reboot the PC..

I *think* shit starts happening when switching resolutions/color depth/vsync while G-Sync is active.

The only way I can safely reproduce it is when I turn vsync on/off ingame in GTA5. Then all sorts of bs starts happening and I have to reboot..

PS: I can't safely say we're experiencing the _same_ issues as I don't have an HDMI 2.1 capable card, but it at least sounds similar..
 
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madpistol

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Powercycle the TV and disabling G-Sync, apply, reenable G-Sync.

I have the same (or at least a similar) issue with my 2070S on HDMI 2.0 on both the .20 and .25 firmwares and also had similar issues on my old Momentum 43" FreeSync.

I think that weird stuff is either caused by Windows 10 or the nvidia drivers.. sometimes I even have to reboot the PC..

I *think* shit starts happening when switching resolutions/color depth/vsync while G-Sync is active.

The only way I can safely reproduce it is when I turn vsync on/off ingame in GTA5. Then all sorts of bs starts happening and I have to reboot..

PS: I can't safely say we're experiencing the _same_ issues as I don't have an HDMI 2.1 capable card, but it at least sounds similar..

But that's where things get "weird". My 2070 Super has NONE of these issues; I can game at 2560x1440 120hz GSYNC and cap the frame rate to 116 in NVCP, and it is smooth all day long, even with HDR. As you pointed out, though, this is HDMI 2.0b, not HDMI 2.1

I also noticed that using the secret FreeSync display on the CX, if you're using a 3080/3090, it goes up to 5.5Hz, but if you're using an HDMI 2.0b GPU (like the 2070 Super), it goes up to 120hz. I really do think that LG still doesn't have this issue completely figured out yet. Worse, I've begun to wonder if this is a limitation of the TV that no firmware will fix. I really hope it isn't, because there are a lot of people that bought a CX with the intention of doing 4k120 HDR and GSYNC once HDMI 2.1 GPUs released.

Well... HDMI 2.1 GPUs are here. Lets go Nvidia and LG. This is your flagship setup (CX + 3080/3090). Prove to the world that a whole bunch of gamers didn't just make a huge mistake by buying into the hype.
 

NM64

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And greyscale isn't perfect either—because I'm not used to a greyscale edge on text, text looks like it has a slight shadow, like it's been over sharpened. Makes my eyes feel like they aren't focused. Again this stands out most on certain colors combos

That soft white shadow on the edge of the 4 and inside the 0? My brain can't not see it
Well then the obvious solution is to turn off cleartype altogether. :p

(I know I know, then you gets jaggies and aliasing out the wazoo)
 

madpistol

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So there is some (slightly) good news.

Apparently GSYNC works fine on the RTX 3000 cards if you use 8-bit color. If you go above that, that's when you start running into the 100-120 FPS stuttering bug.

LG is making progress. Now we just need them to get 10-bit GSYNC 4:4:4 to work.
 

Monstieur

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432
So there is some (slightly) good news.

Apparently GSYNC works fine on the RTX 3000 cards if you use 8-bit color. If you go above that, that's when you start running into the 100-120 FPS stuttering bug.

LG is making progress. Now we just need them to get 10-bit GSYNC 4:4:4 to work.
I'm using 10-bit RGB. Are you sure G-SYNC is active in-game? The CX says VRR even when G-SYNC is not working in-game. Does the G-SYNC Compatible Indicator show up if you enable it? I sometimes have to disable and enable G-SYNC for it to start working.

Try a different game like Dota 2. Pan the camera with the arrow keys - it's a dead giveaway for when G-SYNC is or isn't working. Cap the frame rate in-game with fps_max 110 etc. to test below the refresh rate. When you cap the frame rate at different values, the Hz value on the CX should change.

Also ensure Low Latency Mode is Off.
 

kasakka

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Messages
2,901
compared to an LCD or just in general? it's the nature of cleartype that it adds color to the edges - if you used it on an LCD screen then it works just as well on the CX. I had poor results at first and I thought it might be due to there being a different subpixel layout but after finding and enabling the HDMI Ultra HD Deep Color setting now it looks great and I think the subpixel layout is certainly RGB - if there's an extra W inbetween it mustn't be addressable.
Comparing the OLED with different subpixel antialiasing setups. RGB and BGR have clear fringing that I don't spot on LCDs so the subpixel structure of the CX 48 is not ideal for these. Grayscale works fine to my eyes but took me a bit to get used to it as Windows does a bit of fuckery with it for some fonts on legacy apps.
 

kasakka

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Unchecking the Enable settings for the selected display model checkbox fixes this. You can test for stuttering by looking at the Hz value in the FreeSync Information screen on the CX when running at a constant framerate capped below 120 fps. If the Hz value changes while the frame rate is constant, G-SYNC is stuttering.
Unchecking that box just disables Freesync afaik.
 

steiNetti

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Sep 23, 2020
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But that's where things get "weird". My 2070 Super has NONE of these issues; I can game at 2560x1440 120hz GSYNC and cap the frame rate to 116 in NVCP, and it is smooth all day long, even with HDR. As you pointed out, though, this is HDMI 2.0b, not HDMI 2.1

I also noticed that using the secret FreeSync display on the CX, if you're using a 3080/3090, it goes up to 5.5Hz, but if you're using an HDMI 2.0b GPU (like the 2070 Super), it goes up to 120hz. I really do think that LG still doesn't have this issue completely figured out yet. Worse, I've begun to wonder if this is a limitation of the TV that no firmware will fix. I really hope it isn't, because there are a lot of people that bought a CX with the intention of doing 4k120 HDR and GSYNC once HDMI 2.1 GPUs released.

Well... HDMI 2.1 GPUs are here. Lets go Nvidia and LG. This is your flagship setup (CX + 3080/3090). Prove to the world that a whole bunch of gamers didn't just make a huge mistake by buying into the hype.
I also see the 5.5Hz bug on the VRR hidden osd, spontaniously jumping up and down when I get into the mentioned situations on my 2070S..

I'm starting to get a bit scared that this either isn't fixable or won't get fixed by MS/nvidia/LG (whoever is the culprit).

I've got about a week to return the TV, but I'm almost certain I won't fet another deal for the 55CX for 1200EUR where I live and there aren't any alternatives on the horizon.. :/ I also don't see the 48CX dropping ever in my region, that's about 1600 EUR here - if you can even grab one.. even the B9s are going for 1500+.. hmmm
 

steiNetti

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In my case, unchecking that box makes the Hz value stable with G-SYNC at any locked frame rate below 120 Hz, and the stuttering stops.
Do you constantly hit that locked framerate? Because then it's not G-Sync working, but just no stuttering/tearing due to a stable framerate..
 

Kev13Dd

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Apr 16, 2013
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I also see the 5.5Hz bug on the VRR hidden osd, spontaniously jumping up and down when I get into the mentioned situations on my 2070S..

I'm starting to get a bit scared that this either isn't fixable or won't get fixed by MS/nvidia/LG (whoever is the culprit).

I've got about a week to return the TV, but I'm almost certain I won't fet another deal for the 55CX for 1200EUR where I live and there aren't any alternatives on the horizon.. :/ I also don't see the 48CX dropping ever in my region, that's about 1600 EUR here - if you can even grab one.. even the B9s are going for 1500+.. hmmm
Some people have it working with certain settings combos, as well as with certain games. If it was straight up broken and never seen working, I'd be hesitant. But we know it's possible and we know it's close. I'm not worried
 

steiNetti

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Some people have it working with certain settings combos, as well as with certain games. If it was straight up broken and never seen working, I'd be hesitant. But we know it's possible and we know it's close. I'm not worried
That's what worries me. If it was straight up broken LG/nvidia/MS would have to react.

But that half broken state could easily be dismissed as "good enough, not our problem anymore".
 

Morkai

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So there is some (slightly) good news.

Apparently GSYNC works fine on the RTX 3000 cards if you use 8-bit color. If you go above that, that's when you start running into the 100-120 FPS stuttering bug.

LG is making progress. Now we just need them to get 10-bit GSYNC 4:4:4 to work.
This seems correct.

So I have 3 options currently on the .26 firmware:

1. 4k 4:4:4 120 8Bit g-sync on amd freesync off. Seems more or less flawless in functionality.
2. 4k 4:4:4 120 10bit g-sync on amd freesync on. Needs framecap around 105-106, stutters at higher fps and the functional range isn't full, but works very well around perhaps 80 or 90-105 range, even in HDR.
3. 4k 4:4:4 120 10Bit g-sync on amd freesync off. full functionality but black flashes and needs enabling/disabling until it works, then glitches out randomly, so pretty bad.
 
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CyJackX

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Apr 8, 2015
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Don't own any of the hardware, but just out of curiosity; what are people's sharpness settings with Cleartype?
Sharpness settings add additional contrast to edges; I always turn sharpness to 0 on my current tV.
 

Morkai

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LG has acknowledged the high refresh gsync stutter and has pledged to fix it for CX owners!

https://www.forbes.com/sites/johnar...st-oled-tv-nvidia-rtx-30-glitch/#116be428314b
"This update will not, it seems, be available for roll out quite as quickly as the update that fixed the previous RTX 30 issues; LG’s response suggests that it hopes to have the ‘stutter’ firmware in circulation before the end of the year. "

Anyway, since 4k 120 8bit 4:4:4 g-sync works I'm not too stressed anymore.
 

madpistol

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"This update will not, it seems, be available for roll out quite as quickly as the update that fixed the previous RTX 30 issues; LG’s response suggests that it hopes to have the ‘stutter’ firmware in circulation before the end of the year. "

Anyway, since 4k 120 8bit 4:4:4 g-sync works I'm not too stressed anymore.
I'm just glad they think they can fix it. If they can make 4k120 4:4:4 10-bit HDR and GSYNC all work at the same time without stutter, it will restore my confidence in them for future TVs.
 

SoCali

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Yeah confirming here that going down to 8bit completely fixes Gsync stutter. Such a huge difference.
 

Monstieur

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Yeah confirming here that going down to 8bit completely fixes Gsync stutter. Such a huge difference.
8-bit didn't make any difference. G-SYNC still stutters unless I uncheck Display Specific settings. It runs the same as 10-bit.
 

Kev13Dd

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"This update will not, it seems, be available for roll out quite as quickly as the update that fixed the previous RTX 30 issues; LG’s response suggests that it hopes to have the ‘stutter’ firmware in circulation before the end of the year. "

Anyway, since 4k 120 8bit 4:4:4 g-sync works I'm not too stressed anymore.
This might kick a hornets nest but... can someone explain the downside of 8bit 4:4:4? Is it just some banding and limited HDR? Or is HDR completely disabled
 

mirkendargen

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This might kick a hornets nest but... can someone explain the downside of 8bit 4:4:4? Is it just some banding and limited HDR? Or is HDR completely disabled
You can definitely still run HDR, because you've been able to do 4k 60hz RGB 8bit HDR Gsync on Turing since the TV came out.
 
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Groto

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Jun 1, 2006
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257
Assuming this issue is fixed with the GSYNC stuttering, is that really the last "major" issue with this display? Since they say they will get it fixed maybe I should finally make the plunge and purchase the 48in.
 

madpistol

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Assuming this issue is fixed with the GSYNC stuttering, is that really the last "major" issue with this display? Since they say they will get it fixed maybe I should finally make the plunge and purchase the 48in.
As far as I know, yes. I haven't seen anything else on this TV that's a deal breaker (is the raised-blacks for VRR still a thing?)
 

SoCali

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8-bit didn't make any difference. G-SYNC still stutters unless I uncheck Display Specific settings. It runs the same as 10-bit.
Yes it did because I can switch back to 10bit with that check box off and it's a mess. I tried the check box thing and enabling VRR via Windows 10 over a week ago with no success.

I have it set to 8bit with the display specific settings checked and now the cyclic stutter in Shadow of the Tomb Raider and Hades is gone.
 

Monstieur

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Yes it did because I can switch back to 10bit with that check box off and it's a mess. I tried the check box thing and enabling VRR via Windows 10 over a week ago with no success.

I have it set to 8bit with the display specific settings checked and now the cyclic stutter in Shadow of the Tomb Raider and Hades is gone.
I get extreme stuttering at 8-bit with Display Specific settings checked. Just need to wait for a fix. With the box unchecked, i need to toggle G-SYNC off & on each time my display switches off.
 

sharknice

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Linus finally made a video about our screen :)


I like the part where he compares the pixel transitions between the CX and the 360hz IPS using a 3000 fps camera. On the CX the pixels are essentially fully transitioned in under 1 ms whereas the 360hz IPS takes 6 ms to mostly transition and never really fully transitions to a completely clean background, it looks more like what the OLED does in 0.33 ms.
Basically a slow motion view of all the garbage you see during LCD transitions.
 

Kev13Dd

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Apr 16, 2013
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I get extreme stuttering at 8-bit with Display Specific settings checked. Just need to wait for a fix. With the box unchecked, i need to toggle G-SYNC off & on each time my display switches off.
And I get no Gsync if I uncheck it regardless if the display switches on/off

¯\_(ツ)_/¯

Everyone seems to be having different results. I locked my framerate at 40 and toggled that box on/off while running the same benchmark, and compared videos afterwards to remove my subjective eye-test. When it's unchecked on my PC, there is no VRR, and there is significant stutter at 40fps. With it checked, both the monitor/PC report VRR is active and the stutter is reduced (exactly what Gsync should do)

At this point I'm just glad LG confirms they know about it, because I don't think the rest of the internet is going to reach a collective agreement before they eventually push out a patch
 

MistaSparkul

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I like the part where he compares the pixel transitions between the CX and the 360hz IPS using a 3000 fps camera. On the CX the pixels are essentially fully transitioned in under 1 ms whereas the 360hz IPS takes 6 ms to mostly transition and never really fully transitions to a completely clean background, it looks more like what the OLED does in 0.33 ms.
Basically a slow motion view of all the garbage you see during LCD transitions.

Wish we had 360Hz OLEDs lol. But honestly 120Hz + BFI is really really good already.
 

mirkendargen

Limp Gawd
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435
I like the part where he compares the pixel transitions between the CX and the 360hz IPS using a 3000 fps camera. On the CX the pixels are essentially fully transitioned in under 1 ms whereas the 360hz IPS takes 6 ms to mostly transition and never really fully transitions to a completely clean background, it looks more like what the OLED does in 0.33 ms.
Basically a slow motion view of all the garbage you see during LCD transitions.
Yeah this is why LCD screens above 120hz are dumb. They can't actually transition that fast, it's all just marketing bullshit that leads to a blurry mess of overshoot.
 
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