B580 HDR issue in DIY Monitor

[Mr_Tadokoro]

I am encountering an issue with my Intel B580 GPU when using a DIY display setup. The display consists of a panel (AUO B160QAN02.2) and a pass-through board connected via eDP interface. The pass-through board links to the GPU via DisplayPort (DP)

This pannel support 10bit color + 240Hz +HDR. But the GPU only provides a 6-bit depth potion at 240Hz refresh rate. If forcing 10-bit color by Intel Graphics Command Center, the system automatically enables HDR and locks the refresh rate to 60hz, the display exhibits a washed-out/grayish appearance unless HDR is manually enabled.

The same setup works flawlessly with an NVIDIA GPU, it allowing simutaneous 10-bit, HDR, 240Hz refresh rate without issues.

when using a commercially available display, B580 dose not exibit the aforementiones issue and can support 10-bit color with HDR at 240Hz.

[DhannielM_Intel]

Hello Mr_Tadokoro,

Thank you for posting in the community. It seems you're using a custom-made monitor panel. I have a few clarifications I'd like to address regarding your setup:

1. Are you using an eDP to DP adapter to connect your monitor to the GPU? Is this assumption correct?
2. What is the version of DP connected to the GPU?
3. Could you provide the exact model of your NVIDIA GPU?
4. Are you using the latest driver version for your B580?
5. Is there a direct DP-to-DP connection from your monitor to the GPU?
6. Do you know the HDCP version of the monitor panel you're using?

Additionally, if you have the Intel Graphics Command Center (IGCC), could you generate the EDID of your monitor for further investigation? You can do this by navigating to the Support section and accessing the System Diagnostic panel, where you'll find a button labeled "Generate Report." This will compile all graphics information on your system, including the EDID of your monitor. Please save it as a text file and share it in this thread.

Best regards,

Dhanniel M.

Intel Customer Support Technician

[Mr_Tadokoro]

There r no eDP to DP adapter is usage. The connection path is : Intel B580 GPU → DP cable → Pass-through Board → eDP interface → AUO B160QAN02.2 panel.

The DP interface is DP1.4.

I had tried the RTX 3060 Ti and RTX 4080 Super. The driver Version is 536.67.

I using the latest driver on B580. The driver version is 32.0.101.6734.

A direct DP 1.4 cable connects the GPU to the pass-through board.

I can`t get the datasheet of AUO B160QAN02.2. So I couldn`t know the HDCP version.

Here is the EDID report

By the way, now I can enable 10-bit color depth at 240Hz and activate HDR on my B580. However, when HDR is enabled, the screen will turn gray, just like the display does not properly support HDR. I also try the AMD 9070 XT, is exhibit the same issue. But the NVIDIA GPUs work flaylessly with no color degradation in HDR mode.

[Mr_Tadokoro]

There r no eDP to DP adapter is usage. The connection path is : intel B580 GPU → DP cable → Pass-throu Board → £DP interface →AUO B160QAN02.2 panel.
The DP interface is Dp1.4.
I had tried the RTX 3060 Ti and RTX 4080 Super. The driver Version is 536.67
using the latest driver on B580.The driver version is 32.0.101.6734
A direct Dp 1.4 cable connects the GPU to the pass-through board.
I can `t get the datasheet of AU0 B160QAN02.2. So l couldn`t know the HDCp version
Here is the EDlD report

By the way, now l can enable 10-bit color depth at 240Hz and activate HDR on my B580. However, when HDR is enabled, the screen will turn gray, just like the display does not properly support HDR. l also try the AMD 9070 XT, is exhibit the same issue. But the NVIDIA GPUs work flawlessly with no color degradation in HDR mode.

[MUC]

The EDID shows:

The EDID doesn't necessarily match the required structure. However, the range limits indicate that there is likely a third EDID block that the Intel Graphics Command Center isn't reporting via diagnostics.

2560 x 1600 @ 240 Hz RGB 10-bit CVT-RB = 1174.25 MHz pixel clock = 136% DisplayPort 1.4a HBR3, so DSC is required.

Please run edid-test.exe:

https://www.monitortests.com/edid-test.zip

This will create a file named "edid-test.txt" in the same folder. Please attach this TXT file here.

[Mr_Tadokoro]

I borrowed the B580 to my friend. I will reply in a few days.

[Mr_Tadokoro]

As requested, I have generated the EDID report using edid-text.exe and attached it to this message. Additionally, I have taken photos of the screen output with both the Intel B580 and NVIDIA RTX 3060 Ti GPUs when HDR is enabled.

These images clearly demonstrate the following differences:

• Intel B580 with HDR enabled:

  • Lower brightness compared to the NVIDIA GPU.

  • Noticeably washed-out/grayish appearance, similar to an improperly calibrated HDR display.

• NVIDIA RTX 3060 Ti with HDR enabled:

  • No brightness reduction or color degradation — HDR operates as expected.

Attachments:

1. edid-test(B580).txt (EDID report)

2. B580.jpg (HDR on B580)

3. 3060Ti.jpg (HDR on RTX 3060 Ti)

[MUC]

The EDID test shows, as suspected, a third block in the EDID:

Since this also seems to work with the B580 according to your screenshot, this point seems to be resolved.

Regarding HDR, the result on a display also depends on the type of metadata sent by the source. I know from personal experience that the Nvidia and Intel drivers handle this differently. Intel and AMD drivers tend to use default values for the Luminance Range (MIN/MAX) and Content (maxCLL/maxFALL) Mapping. Typically:

Mastering display luminance:

• Minimum (black level) = 0.01 cd/m² [= nits]
• Maximum (peak luminance) = 1499 cd/m²

Maximum Content Light Level (maxCLL) = 1499 cd/m²

Maximum Frame Average Light Level (maxFALL) = 799 cd/m²

In contrast, Nvidia drivers without metadata from a source file (e.g., a video file) send a ZERO for all of the above values. According to the definition specified in SMPTE ST.2086, ZERO means "not present." The display must then use its own algorithms for luminance range mapping. This varies from manufacturer to manufacturer.

Your display's EDID says:

• Desired content max luminance: 507.620 cd/m²
• Desired content max frame-average luminance: 507.620 cd/m²
• Desired content min luminance: 0.394 cd/m²

Have you tried setting up the display with a Windows color profile? This changes the sent metadata to avoid the problems mentioned.

Microsoft Support: Calibrate your HDR display using the Windows HDR Calibration App

[Mr_Tadokoro]

I have tried the Windows color profile. It can`t solve the HDR issue with B580. As u can see, the photos of screen show that the B580 with HDR is turn "grey". The problem behaves similarly to the following scenario: 

When using a commercially available HDR-capable monitor, if I don`t enable HDR in the display`s OSD menu, but enable HDR in Windows, the screen will turn "gray".  In my DIY setup, even though the panel natively supports HDR, the B580 seems to fail in corrdinating HDR metedata between the OS and the displaty hardware, resuluting in the same "gray HDR" effect.

[MUC]

I can see the difference in your screenshots, yes. The peak brightness is also displayed differently in your Windows display settings:

• Arc B580: 440 nits
• GeForce RTX 3060 Ti: 508 nits

The 508 nits are in the EDID that the display sends to the computer. Where does the Arc B580 get the value 440 from? Are the screenshots from before or after running the Windows HDR Calibration app and activating the Windows color profile? If the color profile doesn't make a difference, you can also remove it again:

Don't forget to restart.

After removing it, does the peak brightness on the Arc B580 show 508 nits again?

[Mr_Tadokoro]

Yes, the Arc B580 show 508 nits again. But the gray issue doesn`t be solved.

During my recent attempt to use the Windows HDR calibration tool, I adjusted the settings as follow:

• Lowered brightness
• Maximized color saturation

The gray issue improved slightly. It seems to be caused by incorrect gamma curve mapping. Is there a way to manually adjust the gamma intensity for the B580 in HDR?

[MUC]

If the displayed peak brightness is now 508 nits again, then the driver's processing of the HDR metadata, referencing the EDID, appears to be basically working. To narrow it down, signal analysis equipment would be needed, which we unfortunately don't have.

For HDR luminance ranges, gamma functions only provide an approximation of perception in specific areas. Therefore, HDR uses a nonlinear transfer function, defined in the SMPTE ST.2084 standard as the High Dynamic Range Electro-Optical Transfer Function (HDR10 EOTF) based on the Perceptual Quantizer (PQ) principle established by Dolby. This cannot be globally adjusted with a slider, which is why there is none.

Have you ever tried to play an HDR video or movie that you know is in the correct format, i.e., has been mastered accordingly? Do the Nvidia RTX 3060 Ti and the Intel Arc B580 look the same in HDR fullscreen mode then? The Windows desktop and SDR-based content like JPEG images can never be displayed at 100% accuracy in HDR mode. However, a gray haze should not appear...