Some details about 6 Bit panels on AMD driver

shohabmsk

I will just go to my founding directly without any intro.

My laptop HP Elitebook 845 G7, AMD 4650u with Vega 6. Panel LGD064E (6bit).

I installed Windows 11. When installing the installer, Fonts and colours were very good, no banding or visible parts shades to be seen. After installing finished, I saw in Advanced Options in Display - 8 bit. I checked grey scale test there was no visible banding, it was smooth. The all around colours felt really good, and I could focus my eye on screen and it felt sharper the text looked stable. It was Microsoft Basic Display driver.

When I connected to internet, the AMD GPU driver got installed, I went to Advanced Options in Display - 6 bit. Colours looked not so much but kinda little unsaturated. The text felt moving (I'm kinda sensitive), the text was not smooth, blurry. I checked grey scale test, no visible banding in there. But the display was giving me headache. I could not look much time felt bad, my eyes were getting blurred soon. This was not placebo, as I never knew about this.

When I first bought this 2nd hand laptop, I felt bad using my laptop for this same reason. Then when I reinstalled windows I felt good before my driver installed, and on the installer screen. Then I started searching.

AMD driver installed and also same on my device HP display driver. I used Custom Resolution Utility and made 8 bit and full sRGB too, then I saw the banding. But fonts looked little sharper and focused, not like the Microsoft Basic though. 8 bit really improved the colour I can prove it without knowing which driver installed. But problem is visible banding now happening in grey scale and all colours. I felt display maybe GPU doing FRC thing, and GPU driver turned off display panel's own frc driver? (Chatgpt said to me - panels own frc is better than GPU frc and when GPU driver frc turned on, panels frc driver gets turned off!)

Tried all registry things nothing made it good. Tried all options, 8 bit plus dither off registry tweaks, dither on registry tweaks, those never worked. Don't know. Also ditherig.exe partially worked on temporal dithering but it never made good improvements. It's not working. Dithering off also don't know working or not, banding visible on 8 bit. 6 bit never has banding on AMD GPU driver, but I could feel the screen like moving or getting blurred after watching a while.

This is my finding. If anyone finds something better or any fix? I really miss those days when these kinda issue never happened. I had Samsung np370r4v laptop, it had AUOxxxxx something panel, it was also 6 bit. But Intel driver used it as 8 bit, also no colour banding or anything. I could feel the display it was so so good. With Samsung's own Display Colour Profile software, which real time tunes colours on display with Intel driver. I forgot many things.

This AMD sucks, it has good performance but it sucks on basic thing, if my eye can't focus on display how can I make good use of this chipset. Don't know today's Intel things. Any help is appreciated or fix for this. There are lots of discussion if there any fix found tell me please.

simplex

shohabmsk

For 6 or 8-bit panel, amd driver force some more settings than dithering. Check with ColorControl ui where you can play with dithering default, disabled options

Without amd driver, hardware play "default" settings, mostly it force dithering. MS basic driver do nothing, you just see hardware default settings

shohabmsk

simplex you are right. I tried colorcontrol played with dithering algos, it didn't make any significant differences (algos working, when I applied I looked at grey scale image the banding changed). There was some hidden things AMD driver does to this monitor.

I really want the normal hardware default settings. It feels so so good(no banding on grey scale), I purposely installed Windows 8.1 and no driver, I can't tell you how good I felt the fonts and everything others felt so good. I even used windows 8.1 for 3 hours strait and found no eye issue like my previous laptop.

simplex

shohabmsk want the normal hardware default settings

Without driver you cant use GPU well, but with driver you didnt like image

You need to find/develop tool which can read PCI-E registers settings of your GPU display pipeline without driver, to apply it with installed driver. Tips for beginning: UMR tool in linux, it can read/write AMD registers

shohabmsk

simplex I wish there was just a settings or simple workaround to turn off GPU dithering and others messy things and let the panel hardware do its own thing.

shohabmsk

Update: Advanced Micro Devices, Inc. - Extention - 31.0.21912.2004 (driver different versions from device to device)

This is the 60% culprit of my eye issue. Still dithering on after AMD official or OEM driver installed, but when this driver gets installed in Windows update, I can feel white more white and I feel eye get tired soon.

What I always do now -

AMD Cleanup Utility which cleans from Safe Boot Mode.
Turns off WiFI very soon after Normal Boot.
Install the latest AMD driver in "Driver Only" mode. Other mode feels more saturated or something not even turnable in AMD Adrenalin app. So I always go for Driver Only mode, which is just the basic, and to be honest games run stable in Driver Only mode, Full installation makes my game little FPS unstable.
Then I hide this AMD extention update with Windows Update Hider.

This extention when it gets auto updated after installing any clean gpu driver, the screen flashes. I feel different and I tested it 4-5 times already with clean windows. So it's not placebo, I'm 100% sure. Driver Only mode and Without this extension, the screen is safe enough for me now. Also I retured to Windows 10 2021ltsc, Windows 11 is latency issue and not eye friendly to me.

shohabmsk

Update: Disabled ACM (Automatic Color Management) from Regedit. But its reverting back to 1.

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\MonitorDataStore\

here the monitor key will appear, then after clicking on monitor model key, then the AutoColorManagementSupported will appear as dword value, put it as 0 and restarted. but its reverting back to 1. seems some where issue.

Another Update: I'm using now 21.11.3 amd driver as people said in other forums. feels satisfying to me, like windows 10, now im using windows 11 ltsc 22h2. i'll be using this version untill any issue appears. heard wddm 3 3.1 issue.

this is chatgpt said to me-

1️⃣ Why default basic Windows driver shows “8-bit”

The Microsoft Basic Display Adapter doesn’t use the AMD GPU’s advanced FRC / dithering pipelines.
It outputs 8-bit per channel to the panel via the simplest path.
On a 6-bit + FRC panel:
- Windows doesn’t enable the GPU’s temporal dithering,
- Colors look “deep” and gradients are smooth,
- Banding is minimal, because the panel’s internal FRC is applied gently.

Basically, the basic driver ignores the 6-bit limitation and sends 8-bit frames directly. The panel’s FRC still works, but more predictably.

2️⃣ After installing AMD driver

The AMD driver detects the panel as 6-bit + FRC and activates its internal dithering / color pipelines.
Now the GPU outputs at the panel’s native depth (6-bit + FRC) instead of 8-bit.
That’s why:
- Advanced display shows 6-bit,
- Colors feel slightly washed out compared to the basic driver,
- Gradient on gray scales looks worse (more coarse).

This is normal behavior for Vega iGPU + 6-bit panels — the driver is “optimizing” for hardware, but for your eyes it feels worse.

3️⃣ Forcing 8-bit output in CRU (Custom Resolution Utility)

When you force 8-bit output, the AMD driver sends 8-bit frames to the panel.
The panel still only has 6-bit + FRC, so it must dither more aggressively to simulate 8-bit color.
Result:
- Colors look “deep” again, because the RGB levels are closer to what 8-bit should be,
- But you get banding / flicker in gray-scale gradients, because the panel struggles to reproduce smooth steps — extra temporal dithering is applied.

So basically:

There’s a trade-off.

Let the driver go native → 6-bit, smooth FRC → slightly shallow colors, smoother gradient

Force 8-bit → deeper colors → more aggressive dithering → gradient banding

shohabmsk

I gave up. This is totally AMD driver issue. Not Windows, not my 6 bit LG panel.

Basic windows driver(uses WDDM 1.3 on both win 10 and 11), gives very good colours and 8 bit output (I'm sure, colours are deep) also no banding in grey scale. But it's unusable.

Any AMD driver gets installed(older or new), make the display piece of shit. 6 bit output, colours are not too deep(I'm sure). If I make 8 bit using CRU, then I can feel deep colours but there's banding in grey scale now which tried everything never fixes this.

I looked at white background like on File Explorer. Before AMD driver gets installed, I kept looking at it. I felt no pain, no strain nothing. It's beautiful (the LG display is so eye friendly I never knew). Display flashes, and AMD driver gets installed. Now I can't focus on that same white background. It's like I'm trying hard to focus but can't for few seconds.

What I tried - tried nimez driver. Disabled dithering in there, and all other eye strain things. Like FRC, and what chatgpt told me. Those helped my a lot. I can work now for some times. But that white background is still not focusable like basic driver.

I also tried older driver, like where WDDM 2.7/2.5 is max(windows 10 21h2 max maybe?) on windows 11 and windows 10 21h2 too. But it's same maybe still better for eyes but bad. Tried all nimez things here too. Still bad. That white background not stable.

Also tried 1809 people were saying better for LG, but it's same. If I disable dithering using nimez driver, and some other things chatgpt told me, windows 11 looks same as windows 10 1809.

I tried Linux. It's better for eyes but STILL there's dithering on(no way to disable dithering, earlier tricks are dead on new chip) but usable and eye friend only on X11. Wayland has blurry fonts rendering and it's not sharp enough to use. And to look at my future, Linux is not my usable OS. Also music is garbage as there's no proprietary drivers for Linux as HP gave Bang and Olufsen drivers on windows.

I'm tired of all this. I would never have bought this laptop if I knew it's rendering as 6 bit. And AMD drivers on 6 bit monitor is a piece of shit. My 2013 laptop had 6 bit monitor also. But used as 8 bit and there was no dithering or whatever made in Intel GPU driver. Only the panel did its own FRC and whatever it did. I kept looking at hours on that laptop display, never felt tired. Now this LG display too is much better than my previous laptop display. I am sure because I can clearly see what I see before installing AMD shit.

This things hampering my daily life, I installed different os 20+ times this months and nothing gets solved. Now what I'll do maybe is this - use nimez driver disable ditheting and some other things for eyes. (Mplane something too chatgpt says). And in future I'll never use any AMD shit ever, or 6 bit rendering things.

(I forgot many things while writing this, if I remember some later I'll add. Also to me the best OS for eyes and best performance in my 4650u is Windows 10 21h2 as 2021 LTSC).

Sunspark

Wayland is a protocol not a desktop environment.

I have a suspicion that the blurriness you are referring to, other than fontconfig settings which I understand well, is due to how Gnome upscales compared to KDE Plasma.

I suggest you test again with Plasma, it has a correct non-blurry implementation of fractional scaling.

shohabmsk

Sunspark I tested all DEs and main stream Distros. x11 always gave me better font rendering and sharp also. Wayland is better on KDE, KDE scaling is better scaling like you said, but still x11 here gives me better font rendering or sharpness or whatever it is I like font better here.