Cannot set 10/12 bit color at 4k60hz on compatible TV with certified 2.1 cable

[DJO_Maverick]

The issue is as described in the subject.  System details:

Driver 32.0.101.8425 (also true with rollback to .8331)

CPU: Intel 12600KF

Mobo: Asus z790 Gaming Wifi7

RAM: 32gb DDR5

Windows 11 Pro 26200.7623

Display: LG B4 OLED

Cable: HDMI 2.1, certified (with multiple different certified cables to be sure)

LG IS set to Game Optimizer on, with input recognized as PC, with Deep Color on, and 4:4:4 passthrough on

Reproduction:

Starting from settings of 3840x2160 60hz with VRR and HDR on and 8bit RGB:

- From IGS Display tab, set Color Depth to 10 bits (or 12 bits) RGB (or YCbCr4:4:4)

- Screen goes black and never recovers

- Windows-Ctrl-Shift-B to reset brings it back; however framerate is dropped to 30hz with HDR and VRR disabled

- Windows will then not allow raising to 60hz; doing so drops res to 1080p

- Only by lowering color depth back down will options become unlocked.

It does appear to be stable at 4:2:2 12 bit color with 4k60hz VRR/HDR. However, the display, the card, and the cable all support uncompressed 10 or 12 bit RGB... ARC refuses to comply with that.  Effectively, it appears to refuse to go above HDMI 2.0 bandwidth limitations?

[JeanetteC_Intel]

Hello DJO_Maverick,

Thank you for posting in Intel Communities.

I understand you're encountering problems when attempting to set 10-bit or 12-bit RGB color depth at 4K60Hz, with the system reverting to lower refresh rates and disabling HDR/VRR. However, I notice that while this appears to be a graphics-related issue, your system details don't include information about your graphics card.

I also want to point out that your CPU (Intel 12600KF) does not have integrated graphics (the "F" designation indicates no iGPU). This means you must be using a discrete graphics card to generate display output.

Please help share the following required information below:

• What specific ARC graphics card are you using in this system? (Make, model, VRAM amount)
• Have you tried clean installation of the latest ARC graphics driver version 32.0.101.8362 using the Display Driver Uninstaller (DDU) to Uninstall a Graphics Driver (on safe mode).
• Is the HDMI cable connected directly to your graphics card or motherboard?
• Could you provide an SSU (System Support Utility) log file? This will help us identify your complete hardware configuration and analyze potential compatibility issues.

Once we have your complete graphics configuration details, we can better investigate the HDMI 2.1 bandwidth limitations you're experiencing.

Looking forward to your reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[DJO_Maverick]

Whoops, didn't put the card in there, ha.

This is on a brand new B580 Limited Edition. 

It was necessarily originally a clean installation because the PC is also a brand new build.  Have now also just updated to yesterday's driver release.

HDMI cable is connected directly to the only HDMI port on the B580.

I will have to get back to you on installing SSU.

Since my original post, I did find one workaround that appears to be stable.  Using CRU, in the HDMI 2.1 block, I lowered the Maximum FRL Rate from 48gbpx (12x4) to 40gbps (10x4).  That one change has allowed me to set any and all modes at 4k60hz (RGB 10 or 12 bit, with HDR and VRR).  With that set, I have not had to reset the driver anymore, and it has been stable in gaming and through multiple restarts.

[JeanetteC_Intel]

Hello DJO_Maverick,

Thanks for the detailed update and great troubleshooting! Your CRU workaround (lowering from 48Gbps to 40Gbps) is very helpful - it shows us exactly what's happening with the bandwidth issue.

Please send the SSU log when you can. This will help us investigate further and potentially find a permanent fix.

Thanks for the detailed testing! I'll look forward to your next reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[DJO_Maverick]

SSU scan attached.

[WeirdestMammal]

I have this issue as well. For some reason windows won't allow anything it thinks won't fit over the standard cords unless the monitor explicitly states that it can do it, but most monitors can only do it in VRR mode so they won't transmit that information to windows. The only work-around I've found is to download CRU (custom resolution utility) and follow some tutorials on how to edit the resolutions on there. I have a dual monitor setup and I was able to get one of my monitors to reset to the correct specs by resetting it over and over again with the windows+ctrl+shift+B method while toggling VRR. The trick is to get windows to refresh the monitors at the same time that VRR is first being enabled on the monitor. This bypasses the issue I mentioned above because windows is checking the refresh rate at the same time that your monitor is enabling VRR. Once you've gotten it enabled you can save the profile on CRU so you don't ever have to go through that again and can import it next time. Doing a clean install of drivers will wipe this, and you'll have to redo it or import the resolution with CRU again. I highly recommend watching some tutorials on how to use CRU as you can edit the settings directly, and your monitor may be more conducive to just editing the settings than mine was. 

@intel please give us back the option to set custom resolution/ refresh rate profiles in the Intel software. Windows does NOT manage them effectively. 

[WeirdestMammal]

As a side note, if you do this method, it can cause some black screens or flashing when you first start up or occasionally randomly. Just do the windows+ctrl+shift+B and it should immediately go away. It usually does it to me when I first start windows and Wallpaper Engine starts up, once I hit it with the keybind it doesn't do it again till the next restart. But I also have rgb+12bit in 4k@120+ so kinda worth it. 

[MUC]

The Intel Arc A-series comes standard with an HDMI 2.0b interface with Transition-Minimized Differential Signaling (TMDS). The maximum possible modes on a CTA-861-compliant TV are:

Resolution	Refresh Rate	Color Model	Color Depth	TMDS Clock	Data Rate
4K	60 Hz	RGB	8 bpc	594 MHz	18 Gbps
4K	60 Hz	YCbCr 4:2:2	12 bpc	594 MHz	18 Gbps

According to the HDMI specification, cable transmission of YCbCr 4:2:2 is forced to take place with 12 bpc.

Common modes in consumer electronics:

Resolution	Refresh Rate	Color Model	Color Depth	TMDS Clock	Data Rate	Examples
4K	60 Hz	YCbCr 4:2:0	10 bpc	371 MHz	11.14 Gbps	TV shows
4K	24 Hz	YCbCr 4:4:4	10 bpc	371 MHz	11.14 Gbps	movies
4K		YCbCr 4:2:2	12 bpc		max. 18 Gbps	Dolby Vision (LLDV)

However, some Intel based graphics cards have an additional chip on the board that has a DisplayPort Main Link to the GPU and converts this into an HDMI 2.1 Fixed Rate Link signal. This was standard on Intel's own A770 and A750 Limited Edition cards. For all other A-series cards, the integration of this additional chip (protocol converter = PCON) was at the discretion of the card manufacturers. The Intel B-series comes standard with HDMI 2.1 FRL.

Alternatively, you can use a protocol converter cable and connect it to one of the DisplayPort outputs. This will perform a conversion from DisplayPort HBR3 up to HDMI 2.1 FRL 48 Gbps.

Product	Chip Type
Club 3D CAC-1087	Synaptics VMM7100	3 m / 10 ft	support@club-3d.com
UGREEN	Chrontel CH7218	2 m / 6.6 ft

If you already have good certified HDMI cables, then that will also work for 4K @ 120 Hz RGB/YCbCr 4:4:4 10 bpc :

UGREEN 8K DP > HDMI adapter

TVs don't have DisplayPort. However, if you're using a monitor, always connect it using the DisplayPort protocol whenever possible:

DisplayPort > DisplayPort
Thunderbolt/USB Type-C > DisplayPort

[DJO_Maverick]

It's a B580, which does use 2.1, so that's not the issue I'm afraid.  Sorry I neglected to mention the model originally.

[JeanetteC_Intel]

Hello DJO_Maverick,

Thanks for sharing the SSU log file. Could you please perform another system scan using the latest Intel® System Support Utility (SSU) version 4.3.2? This updated version includes a new feature for capturing raw EDID data, which is essential for our current investigation. You can download the latest tool here: Intel® System Support Utility for Windows* (version 4.3.2).

Once completed, kindly send me the new log file.

I look forward to receiving the updated log file to continue with the analysis.

Best regards,

JeanetteC.

Intel Customer Support Technician

[DJO_Maverick]

432 log attached as requested.  Now this one was taken as-is, with the CRU emulated EDID in place...  just let me know if you need me to disable the workaround as well.

[MUC]

In my opinion, you can keep the CRU change if it works for you.

4K @ 120 Hz RGB / YCbCr 4:4:4 10-bit (HDR) CTA-861 = 40 Gbps

Attempting to send RGB 12-bit is pointless, as the LG panel can't process it anyway. It's a 10-bit panel.

@ Intel Graphics Team: More interesting for driver compatibility is the fact that the driver seems to have problems when 48 Gbps are advertised via EDID. For replication attempts in the lab, I've attached the original EDID from an LG G4 (48 Gbps and w/ DisplayID).

[JeanetteC_Intel]

Hello DJO_Maverick,

Thank you for providing the updated SSU log file. I will continue with the analysis and will update you promptly once we have any new information.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello DJO_Maverick,

Please be advised that I am still working on this request and I understand that you wanted the Intel Arc B580 to output 4K 60 Hz with HDR + VRR using 10‑bit (or 12‑bit) RGB or YCbCr 4:4:4, without the screen blacking out. However, I would like some clarifications below.

•  When you mentioned "Screen goes black and never recovers", I want to confirm that you mean the display never returns until you apply your workaround. Your workaround involves using CRU to lower the Maximum FRL Rate in the HDMI 2.1 block from 48gbps (12x4) to 40gbps (10x4). This change allows you to set 4K60Hz modes (RGB 10 or 12 bit, with HDR and VRR) and has been stable in gaming and through multiple restarts.
• Please provide a short clip of the issue if possible

Looking forward to hearing from you soon.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello DJO_Maverick,

Did you get a chance to review the previous post?

Please let us know if you have any questions.

Best regards,

JeanetteC.

Intel Customer Support Technician

[DJO_Maverick]

Apologies for slow response, didn't see this;

No, when I say it goes black and never recovers, I mean the screen goes black and never restores an image without restarting the driver.  Using windows-ctrl-shift-B restarts the driver in a fallback mode...  typically same res/bit depth but dropped to 30hz.

Since applying the CRU workaround described, it has never happened.

[JeanetteC_Intel]

Hello DJO_Maverick,

Thank you for the update, and no worries about the response timing.

I appreciate you clarifying the issue behavior - where the screen goes completely black without recovery, requiring Windows+Ctrl+Shift+B to restart the driver, which then falls back to 30Hz mode.

It's good to hear that the CRU workaround has been effective in preventing the issue from reoccurring.

I'll proceed with investigating this issue further on our end and will share an update once more information becomes available.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello DJO_Maverick,

I'm still working on this issue however, I realized that we already released new driver, version 32.0.101.8509 (WHQL Certified). Can you please try to proceed with a clean installation using DDU uninstaller (in safe mode) and let me know how it goes?

Please share a new SSU log file and short video clip with this new driver installed if the issue still persists.

Looking forward to your reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello DJO_Maverick,

Did you have a chance to review the previous post? 

By the way, Intel release new driver, version 32.0.101.8531. Please proceed with a clean installation using DDU uninstaller (in safe mode) and let me know how it goes.

Kindly share a new SSU log file and short video clip with this new driver installed if the issue still persists.

Looking forward to your reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[DJO_Maverick]

After resinstalling with ~.8531 and uninstalling my CRU EDID fix, the behavior is unchanged.  Video dropped momentarily, then Windows locked me out of the desired settings combo.  If 10bit RGB is set in Intel controls, setting to 60hz in Windows drops me to 1080p; raising back to 4k drops me to 30hz.

Restoring the CRU tweak still solves the problem.  I'm also attaching a copy of the specific CRU settings I'm using to fix it on my end (working backup.bin).

I apologize that I'm honestly a bit fuzzy on exactly what of that behavior you want a video of...?

[JeanetteC_Intel]

Hello DJO_Maverick,

Thank you for sharing this update.

Regarding the video request, please record a short video showing the issue you described:

• The momentary video drop when changing display settings
• Windows locking you out of the desired settings combination
• The resolution/refresh rate behavior (dropping to 1080p at 60Hz or 30Hz at 4K with 10-bit RGB)

This will help us document the problem that occurs without your CRU fix in place.

I look forward to hearing from you.

Best regards,

JeanetteC.

Intel Customer Support Technician