Intel NUC11 dual monitor problem

EdwinPouwel · ‎02-03-2022

Hi,

Since saterday I have a Intel NUC11TNH-7 with 16Gig of RAM. This NUC has 2 HDMI's outputs and 2 Thunderbold outputs.

I connecten 2 Asus monitors to the NUC, both are exactly the same. Both monitors can handle a resolution of 2560x1440.

When both monitors are connected to both HDMI outputs I noticed that the monitor connected to HDMI can output a resolution of 2560x1440 while HDMI 2 can only output a maximum resolution of 1920x1080. I checked Windows 10 and 11 and both show this problem.

HDMI 2 can output a maximum resolution of 1920x1080. All drivers are updated.

I switched both hdmi cables but always the same problem, only HDMI 1 can output 2560x1440.

What can I do wrong? Please advice.

Best regards,

Edwin

LeonWaksman · ‎02-03-2022

Hi Edwin,

Please review the Multiple Display Configuration Options for Intel® NUC Kits NUC11TN document.

Leon

EdwinPouwel · ‎02-03-2022

Hi Leon,

Many thanks for your replay.

Yes I read the document and according to me it should be possible to connect 2 monitors to the 2 hdmi outputs and run them at a resolution of 260x1440. Or am I wrong? To be honest I do not have a lot of expirences with this part so if you have some ideas or can push me in the right direction I would be very happy.

many thanks and best regards,

Edwin

LeonWaksman · ‎02-04-2022

Hi Edwin,

With 16GB of RAM, maximum 8GB is assigned for Graphics Memory. 1080P display requires 2GB - 6GB of VRAM (in most cases 4GB).

1440P display requires 4GB-8GB of VRAM. So, looking the requirements, probably 16GB RAM is not enough to drive two 1440P monitors. Anty way, I suggest to wait for confirmation from Intel or other users.

Leon

Edit:

On the second thought, I think that must be something wrong in your NUC. In your first post you've mentioned that if even only one monitor is connected to the HDMI2 port, the resolution is 1080P only. So, in this case it is not a result of low memory size.

EdwinPouwel · ‎02-04-2022

Hi Leon,

Thanks for your answere. Fort sure it is not the ram. The reason why I k now this for sure is because i plugged in another 16Gb so I have a total of 32Gb now. But no difference.

I tryed Windows 10 and 11 and both have the same result. I tried an other monitor but same result.

Hopefully Intel will have a solution.

Best regards,

Edwin

CVV · ‎02-04-2022

Hi, I also experienced problems with the hdmi outputs of this model.
In one of them, everything seemed to work correctly but I didn't have the option to change the quantization range and the problem is that it detected it wrong and configured it to limited. And the other output gave me the option to set the quantization range but I had problems with the resolution and hertz changes.

JRS1 · ‎02-04-2022

@CVV wrote:
Hi, I also experienced problems with the hdmi outputs of this model.
In one of them, everything seemed to work correctly but I didn't have the option to change the quantization range and the problem is that it detected it wrong and configured it to limited. And the other output gave me the option to set the quantization range but I had problems with the resolution and hertz changes.

Yes, I noticed this model has serious problems with HDMI-ports. Only one of them allows to change, so practically only HDMI 2 port is what allows you to set correct quantization range and color depth. Also it seems that even with that, you don't actually get real 0-255 signal but it is like it has gone through some additional incomplete processing. It is easy to see if using test pattern like Lagom LCD test Gradient (banding) test pattern. Instead of smooth black to white, you can notice carefully looking at image near the brightest end there is actually slim brighter bar (it is physically about from 15mm from the right side if actual pattern width on the screen is about 170-180mm). Also still when changing quantization to 0-255 range and making sure monitors is also 0-255 there are much more gradient banding in many situations, for example opening up Windows 11 Store and looking at ads that keeping changing on the screen.

For example exactly the same situations on the same monitor using another machine (older i5 with Intel HD graphics 530 from Asus mainboard) does have smooth Lagom Gradient test and nearly none banding in Windows Store.

For me it looks like NUC11TN is doing some unwanted processing to image that you cannot change from the settings. Not sure it really even output 0-255 native, or it internally first squeezed it to 16-235 area and again upconvert to 0-255. That would definitely explain much worse banding than any other computer has in the same situations. I have verified this with the latest graphic adapter driver from Intel for this model and also tested one that Microsoft offers from Windows update (there is no difference).

Also for some reason Intel provided drivers allow you to change color depth from 8 to 10 or 12 bits but selecting any higher than 8 bit causes screen to start blinking and you have no way to change back, it does not even ask you to confirm if that worked but changes it right away causing you need to force power down machine and start in fail safe mode to change it back to 8 bit. Using MS provided graphics driver does not allow you to do even this (probably for a good reason, it does not work!).

Anyone at Intel actually testing these things?

EdwinPouwel · ‎02-04-2022

This sounds not good. In my case I can set HDMI 1 to the higher resolutions. HDMI 2 can not go higher then 1920x1080.

All my monitors can handle a resolution of 2560x1440.

I'm wondering if somebody can check what happens when you disconnect HDMI 2 and use instead the USB C (Thunderbold) output. I have no cable so i can not test it.

Any one?

Best regards,

Edwin

EdwinPouwel · ‎02-04-2022

Sounds like there is a problem with a firmware version or driver.

Hopefully Intel can help.

Edwein

EdwinPouwel · ‎02-05-2022

Hi, are you able to check it with the Thunderbold output? I have not such a cable so I can not test it but maybe youy have such a cable?

Best regards,

Edwin

JRS1 · ‎02-05-2022

@EdwinPouwel wrote:

Hi, are you able to check it with the Thunderbold output? I have not such a cable so I can not test it but maybe youy have such a cable?

Best regards,

Edwin

Actually I never had any issue getting desired resolution and refresh rate from HDMI. Mine give 4K@60Hz from either HDMI as well as from USB-C. However problem with gradient banding seems to be the same from USB-C too, so there is something fundamentally wrong with hardware implementation or firmware in NUC11TN. I only have one display, so cannot test for more displays.

Also it is absolute nonsense that you would need 4-8GB VRAM for 1440p! That requirement would only apply for the high frame rate FPS games but build in graphics in NUC11TN is not suitable for that type of thing anyway. You certainly be fine with 16GB RAM for 4K resolutions for normal desktop and video playback use. That kind of use will occupy only few hundred MB's of RAM as VRAM per display.

EdwinPouwel · ‎02-05-2022

Hi,

Thanks for the explenation. Yes I think it is a firmware issue (I hope). Hopefully Intel will fix this soon.

best regards,

Edwin

EdwinPouwel · ‎02-06-2022

Very interresting...

I did some more testing via the Intel Graphics center. Here I noticed something very strange.

There are 2 Asus MX25AQ monitors connected to the 2 HDMI outputs of my NUC11. They can both handle a resolution of 2560x1440.

NUC, HDMI 1 -> can do the resolution 2560x1440

NUC, HDMI 2 -> can only do a maximum resolution of 1920x1080.

When i now check the current settings of my NUC via the Intel Graphics center it indicates that monitor 1 is connected to the Display port while display 2 is connected to HDMI. See the attached pictures. But this is not correct, they are both connected to the HDMI outputs.

Very strange.

JRS1 · ‎02-06-2022

@EdwinPouwel wrote:

Very interresting...

I did some more testing via the Intel Graphics center. Here I noticed something very strange.

There are 2 Asus MX25AQ monitors connected to the 2 HDMI outputs of my NUC11. They can both handle a resolution of 2560x1440.

NUC, HDMI 1 -> can do the resolution 2560x1440

NUC, HDMI 2 -> can only do a maximum resolution of 1920x1080.

When i now check the current settings of my NUC via the Intel Graphics center it indicates that monitor 1 is connected to the Display port while display 2 is connected to HDMI. See the attached pictures. But this is not correct, they are both connected to the HDMI outputs.

Very strange.

Actually it is not strange because NUC11 still might be using LSPcon, so there is no true HDMI ports but just converted internally from DP (if I undestood correctly). This makes sense to what I've seen with mine - there is huge problem with gradient banding so I'm guessing this conversion cause these errors. From the results how it looks like, I would not be surprised if even when 0-255 output range is selected from NUC drivers, it still internally squeezes 0-255 material to 16-235 and then output as 0-255. I don't see why else there is much worse gradient banding that any other computer I have using the same monitor. Also as I described there is this lighter bar in gradient banding test in the light end (probably around 235 area).

JRS1 · ‎02-06-2022

Seems that NUC11TN technical product specifications confirm this. See page 24 for diagram.

https://www.intel.com/content/dam/support/us/en/documents/intel-nuc/NUC11TN_TechProdSpec.pdf

EdwinPouwel · ‎02-06-2022

Hi JRS1,

I'm not an expert but what I read in the Intel NUC documentation is that you can connect up to 4 monitors with a maximum resolution of 3840x2160, see https://www.intel.com/content/www/us/en/support/articles/000059049/intel-nuc.html

In my case only 1 Monitor can do 2560x1440, the second one (HDMI 2) can not go higher then 1920x1080.

So that is not correct accordig to me.

Best regards,

Edwin

JRS1 · ‎02-06-2022

@EdwinPouwel wrote:

Hi JRS1,

I'm not an expert but what I read in the Intel NUC documentation is that you can connect up to 4 monitors with a maximum resolution of 3840x2160, see https://www.intel.com/content/www/us/en/support/articles/000059049/intel-nuc.html

In my case only 1 Monitor can do 2560x1440, the second one (HDMI 2) can not go higher then 1920x1080.

So that is not correct accordig to me.

Best regards,

Edwin

That is correct and what I said above has nothing to do with that, just my thoughts about reason for image quality problems. Your NUC should be able to give you 2560x1440 easily for both monitors.

Does your NUC make coil whining sound? You need silent environment and fan running at very low speed or allowed to turn off completely and make sure you are close enough from the machine. Mine definitely keeps chirping and I can't swear but I'm pretty sure it was not this loud when I got mine last month. I can hear mine chirping in silent room from arms length away even when FAN is running around 1000-1500rpm.

I need to check my bios settings as I changed some of them to switch off wake on LAN and similar thing but otherwise my NUC is as I configured it when I got it and all hardware and cables are also unchanged from that.

EdwinPouwel · ‎02-06-2022

I can hear the fan running but it is not making a lot of noise. Maybe you have a problem with the fan it selves?

regards,

Edwin

JRS1 · ‎02-07-2022

@EdwinPouwel wrote:

I can hear the fan running but it is not making a lot of noise. Maybe you have a problem with the fan it selves?

regards,

Edwin

No, it is definitely not from the fan but coil whine. How long you have had yours? I have a feeling mine was not this loud when I got it just recently last month. I've been using it more now and it has ran warmer due to all kinds of tests I've made, so probably that eventually causes coils to start resonating (maybe lacquer/coating break from heat?). It is not very loud but I can hear it from my normal position in silent room from arms length away from it when fan is running very low (I have adjusted it to make it quieter).

Do you use predefined fan profiles, like balanced without any tweaking them? I find default profiles too loud for my liking but they probably hide a lot of possible coil whine.

JRS1 · ‎02-07-2022

Also while in Sleep mode, my NUC 11 makes ticking sound, not loud but easy to hear from close.

EdwinPouwel · ‎02-07-2022

I used the ‘Balance’ mode. Are you sure that it is the fan? Because you mention that also in sleep mode you do here noise. Is the fan running in sleep mode? Is it possible that a component is resonating? I had this with one of my desktop PC’s.

best regards,

Edwin