Why 5120x1440 Doesn't Work with Apple M1

So far it does work for me at least somewhat. I can run it in full 120Hz without any issues to wakeup wit DP 1.2 but no joy with DP 1.4 neither in 120Hz or 60Hz. Tried SwitchresX Beta where I had to disable System protection (and I rather don't wanna do it) but also no change. DP 1.4 is just not working so far.

Also with System Protection disabled I cannot run iOS Apps where I rely on some Apps which aren't working for the M1 Processor yet.

That's fair, personally i think this is not really a hardware-blocked issue, since it does work (with somewhat convoluted steps). I think if Apple is made aware, and enough people encounter this, a software/firmware fix should be quite realistic without having to wait for an upcoming generation of new hardware.

Have you tried my solution ? it works perfectly at home I also have a samsung 49" and I work with a resolution of 5120x1440p with 120Hz

Just install a small application available here: https://github.com/Eun/DisableMonitor

It’s the warning that comes with the app that worries me....

”It has been reported that the software is able to cause irretrievable damages to your computer.

Use at your own risk!

The project development has been stopped and won't be continued, if you want to be a maintainer consider opening an issue.”

I don't think this is a real problem, the repo owner put this message to clear himself of any responsibility.

By default, only with the Apple settings it is possible to activate 5120x1440 120Hz with the following procedure, but just after disconnecting from the screen or rebooting the setting is not kept, the GitHub repo just allows to go faster. So I think this is not a hardware constraint, but just an optimization problem. After all it worked fine with an Intel 2020 MacBook Air.

To succeed without software just disable the FreeSync, hold the option key and select 5120x1440 and then in the screen settings change from 60hz to 120hz. Select 120 in the input "Refresh Rate" You will see that the resolution of 5120x1440 is kept and the frequency is 120hz. (in the setting the resolution of 5120x1440 will not be displayed in the list).

Try holding option when from the monitors window. You’ll see detect display show up. I have 2 Samsung 1440p vertical monitors for coding on a 2018 iMac. The monitors are awesome but constantly tweak out from time to time. Going to settings > displays > then hitting option you’ll see the bottom right corner will swap to say detect display. Thanks for the input on the g9 though I’m looking at pairing it with the new MacBook Air via a brydge dock when that comes out next month.

So Apple completed a variety of diagnostics. They want me to bring in my monitor and leave it so they can run a few tests. I was told that this was normally not allowed (leaving non-apple devices behind, so hopefully it helps the diagnosis of the issue. I can see from posts that this is happening on various monitors but Apple does not see it as an emerging issue (such as the pink squares) since not enough folks are raising formal support requests. I urge you all to do so while I sacrifice my monitor 7-10 to help the greater cause. Put in your tickets. Get it on their radar.

I’ve been like that for a couple of weeks and it works fine 95% of the time.

As a matter of interest do you get “5120x1440” or “5120x1440 Low Resolution” - Can’t tell what the difference would be as 5120x1440 is 5120x1440.

Are you 60 or 120Hz?

When I had to select initially the resolution, the option shown was only "5120x1440 (low resolution)". When i checked later on, it was showing just "5120x1440". I just checked again now and "5120x1440" disappears from the list, as soon as I access the "Display" windows, from System Preferences. It literally disappears 0.1sec after opening the Display window... Very strange. Good thing though is that the resolution is not affected and keeps on working at 5120x1440.

@ratephi,

But not at 120hz, nor HDR? (NOTE: not sure the LG 39wL95C handles HDR)

So downgrading to DP1.2 doesn't give you the full functionality of your monitor which is well below the Apple described specification in resolution, frequency and dynamic range. I would not calling that "haven't really experienced any issue at all" as you are working around reproducing some of the actual issues.

I am not saying this isn't a good compromise, just doesn't resolve the fundamental issue.

After hours of working with Apple, we were not able to diagnose the cause between the M1 and Sam CGR90. I had no choice but to return my Mini M1 today. If the Big Sur beta 11.1 really does help I will likely pick another one up, but AFAIK the release notes with 11.1 don't identify any major DP or graphics fixes that I can see.

I'm working at 60hz. I can activate HDR no problem (although after trying it I didn't like it so ended up disabling).

What is it exactly that I'm giving up by using at DP1.2 instead of DP1.4? Resolution is 5120x1440 and frequency is 60hz (which are anyway respectively max resolution and max refresh supported by my monitor). I'm not sure about dynamic range but if by that, you refer to HDR, I have also access to that feature without apparent issues (other that I don't like the image I get out of it, at least for office use).

Just received my Mini M1 16GB/1TB today and can confirm that with the Cable Matters cable/adapter combo that I posted on page 1, and here again for reference: https://www.amazon.com/Cable-Matters-DisplayPort-Resolution-Support/dp/B08C9NPC2S everything works perfectly.

It booted up and recognized my AOC AGON 49" Ultrawide's 5120x1440 native resolution but at 60hz. I simply went into display settings and selected 120hz which was available without any special keypresses or other software.

So for anyone looking for an Ultrawide that works at its advertised specs, take a look at the AOC along with the cable/adapter combo that I linked above.

Good luck everyone, this new Mac is a treat so far!

Did this cable fix the problem?

Edit: was asking in regards to this one previously recommended. https://www.amazon.com/gp/product/B08B3XNZGS/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

Looking at the reviews on amazon, it appears that this cable will work with the Samsung CRG9 Display at 5120x1440

 Works with M1 Mac mini and 5120X1440 Ultrawide 

By Adam… on December 4, 2020

This was the first cable I got to work with Mac mini M1 and Samsung CRG9 at 5120x1440. Still required some fiddling in settings on both the monitor and the Mac. Hoping for a software update to resolve all of that, but this alone is working well enough, for now.

MacOs 11.1 seems to solve some display issues (Macbook Air M1 + LG 49WL95C-W) but now the big problem is monitor constantly waking up and power off every 2/3 minutes when I put the MacBook on Sleep. So, I have to completely shutdown the Mac every time. Any solutions about this?