Max refresh rate for Intel Iris Xe on 1195G7 CPU

[SF_B]

I bought a used Dell XPS 13 9310 with the 1195G7 CPU and the corresponding Intel Iris Xe GPU.

My monitor supports 75Hz but connecting the laptop with the USB-C 3.1 (displayport alt mode) cable only let's me set 60Hz. There is no 75Hz option.

I used to connect a Macbook M2 and it worked with that cable with 75Hz.

I'd like to know if this GPU even supports 75Hz at the monitor's native resolution of 3840x1600. I'd say yes as the max resolution is 8k@60Hz so with lower resolutions higher refresh rates should be possible.

So why can't I set this refresh rate on this Dell or with this GPU? Latest Intel graphics driver is installed.

[Mike_Intel]

Hello SF_B,

Thank you for posting in Intel community Forum.

For me to further check this, please help provide the following details:

1. Have you tried other cables like HDMI or Display port?
2. Have you also updated the driver of the Graphics?
3. What are the other troubleshooting steps that you tried so far?

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

Thank you for replying.

The Dell laptop only has 2 Thunderbolt 4 USB-C ports. So HDMI is out of the question. So far I used a USB 3.1 USB-C to USB-C cable with Displayport Alt Mode which worked with 75Hz on the Macbook but only gives 60Hz now, as I already mentioned.

I bought a USB-C to Displayport cable just now, tested it and it works! That answers the question if the Iris Xe GPU supports refresh rates higher than 60Hz but unfortunately doesn't solve it for me. I don't wish to connect two cables, one for the display and one for the monitor's hub and power delivery. I want it to be one cable just the way it worked with the Macbook at 75Hz.

I also got a USB-C to USB-C Thunderbolt 4 cable. But that still does not allow me to set anything beyond 60Hz.

The Intel Graphics Driver is up to date 32.0.101.6556. Why can't I use the USB-C to USB-C cables (USB 3.1 or Thunderbolt 4) for 75Hz? The issue exists with a Linux install on the same laptop, too.

As I did not change the monitor settings (doubt it's even possible in that regard) I assume this must be a driver issue for the GPU.

[Mike_Intel]

Hello SF_B,

Thank you for the update

The question if the Iris Xe Graphics can be set to 75Hz has been answered.

However, the issue is with the ports and its supported cables and display configuration.

Have you tried contacting Dell for the supported display and cables for these ports?

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[Mike_Intel]

Hello SF_B,

I hope this message finds you well. 

Were you able to check the previous post?

Please let us know if you still need assistance.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

I will let you know shortly.

[SF_B]

OK, I did some more or less extensive testing. I borrowed a Macbook M4 and another ultrawide monitor, also from Dell. This monitor allows 100Hz. I could confirm my earlier findings from memory that the Macbook uses 75Hz with the original cable and the Asus monitor. Also, with the Dell laptop I could get 100Hz on the Dell monitor using either cable, the one I have always been using with the Asus monitor and the one the Dell monitor came with. This rules out any issues with the cable. From now on I will only talk about the Dell laptop, the original USB-C to USB-C cable with Displayport Alt Mode and the Asus monitor. Macbook, Dell monitor or other cables won't play a role any more.

On the Dell laptop I am running Linux atm (Manjaro) but I ran Win11 before that and the issues were the same. So, in Linux, I retrieved the edid information. That's the information the monitor returns about modes it supports and other data. The decoded output is attached as a text file.

Here's my explanation of the data:

card1-eDP-1 is the built-in laptop monitor. All good with that one. Then card1-DP-3 is the external monitor. It has TWO edid blocks! And the correct information about 75Hz at 3840x1600 is also there, called "Detailed Timing Descriptor" DTD 4. It's in the second block called CTA-861 Extension Block.

From this point of view it seems to me that the Intel driver, on either Linux or Win11, doesn't seem to be able to handle this information (while the Apple driver can). In the OSes I only get the option to set DTD 1 which is in block 1. Seems like a bug in the driver. I tried both drivers on Linux, i915 and xe.

I hope you can make some sense of it and fix the driver! Let me know if I can provide more logs.

I can provide the binary edid file, too, I you need it for testing.

[Mike_Intel]

Hello SF_B,

Thank you for the update and very detailed test.

Just to check, have you tried checking this issue with Dell?

They may also have their own driver to enable the changes or modification if they made some on the Graphics.

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

Hi,

Dell uses the regular Intel Graphics Driver, it is part of the preinstalled Windows installation. Also, there is no other option for the GPU on their Downloads page.

Furthermore, they want me to pay for anything even just a small support question as the support period ended for me.

Would be great if you could investigate.

Best regards

[MUC]

3840 x 1600 @ 75 Hz RGB 10-bit = 85% HBR2

So it's not a problem with the available video bandwidth. However, DTD 4 contains a parameter that differs from Coordinated Video Timing - Reduced Blanking (CVT-RB2). This shouldn't be the real problem, because DTDs (Detailed Timing Descriptors) are explicitly designed to advertise the desired signal parameters to the graphics card and its driver.

According to the EDID, the monitor is an Acer CB382CUR that accepts DisplayPort HBR2. The Tiger Lake platform can, in principle, output such a signal via USB Type-C. For some reason, the driver thinks it shouldn't offer DTD4 with 75 Hz.

As soon as my simulation environment is working again, I'll use the Acer EDID to advertise it to my NUC11 (i7-1185G7). We'll see what happens.

[SF_B]

I've attached the binary edid file for the Asus monitor as a zip file.

Thank you very much!

[MUC]

I can select 75 Hz with this EDID without any problems.

It is worth mentioning in this test, however, that HDR apparently only supports 8-bit with dithering, although the bandwidth would also be sufficient for 10-bit and the EDID in the first block explicitly indicates this.

[SF_B]

So you are using an Intel NUC, right? Does it use a different Intel Xe unit or what could be the cause?

[MUC]

Yes, I use a NUC11TNKv7

Intel Core i7-1185G7 (Tiger Lake-U), Intel Iris Xe Graphics 96EU

I can also successfully output 4K @ 120 Hz RGB (1180 MHz pixel clock) and 8K @ 60 Hz YCbCr 4:2:0 (2376 MHz pixel clock) via the Thunderbolt/USB Type-C port. Both modes fully utilize the DisplayPort HBR3 protocol at 32 Gbps.

Unfortunately, I have no suggestions for your issue at the moment.

[Mike_Intel]

Hello SF_B,

Thank you for for the update

Can you try to install or re-install the latest driver using DDU method.

Kindly refer to the link below for the steps and the link of the latest driver:

https://www.intel.com/content/www/us/en/download/785597/intel-arc-iris-xe-graphics-windows.html

https://www.intel.com/content/www/us/en/support/articles/000091878/graphics.html

If you are still having the same issue, please help generate the SSU logs of your system for me to do further investigation.

Please refer to the link below on how to generate the SSU.

https://www.intel.com/content/www/us/en/support/articles/000057926/memory-and-storage.html

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

I can do that later this week.

[Mike_Intel]

Hello SF_B,

I hope this message finds you well.

I also wanted to further investigate this issue, let me ask if you were able to try my last recommendations and SSU logs that I requested?

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

As I stated before, the laptop is running Linux. I'd have to install Windows first. I can do that once I have time for it, probably next weekend.
I'm definitely investigating this further as well, just don't have that much time atm.

[DhannielM_Intel]

Hi SF_B, 

Thank you for providing your update. We look forward to receiving your findings and the SSU logs.

Best regards,

Dhanniel M.

Intel Customer Support Technician

[Mike_Intel]

Hello SF_B,

I hope you are having a good day.

I am just making a follow up on the SSU that I requested.

We have an SSU for Linux, please refer to the link below:

Intel® System Support Utility for the Linux* Operating System

If you have questions, please let us know. Thank you.

Best regards,

Michael L.

Intel Customer Support Technician

[SF_B]

Good to know. I'll see to it soon, I'm just a bit swamped atm.