Why 5120x1440 Doesn't Work with Apple M1

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?

@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 forget it.

if Apple want to solve this problem, they will solve it on Mac Mini 2018.

They just don’t f__king care about your thought. I had Mac mini 2018 and M1 Mac Mini, both not working with CRG9/Oddessey G9, returned both Mac.

Agreed. Same here it works fine for me. Only "issue" if you want call it so, is that the Monitor wakes up late during a reboot or boot. Wakes up when already reached the desktop. No big deal I'm not keen to see the loading bar. On the other hand no issues when waking up from sleep, no diconnects or whatsoever. Although I have to use Switchresx, without it I get only Low Res Picture (running 120Hz)

I am running an LG 49WL95C-W with a 2017 MBP and get full resolution (5120x1440 @ 60HZ) via type-c only. I have been looking at the M1 Mini but came across this thread and obviously have concerns digging through all the posts.

Can anyone confirm successful resolution not needing SwitchResX and using single clean setup via type-c?

This is crazy! I love my UltraWide and have a very clean minimalistic one cable solution paired with my MBP, this work around would drive me insane!

Very unfortunate, I want a mini mounted under my desk but I will not be able to make this move until Apple finds a solution to this problem.

hey I'm using the same set up - Samsung 49 inch + M1 Mac mini + Switchres X

when I add a custom scaled resolution and after rebooting, it shows "not active - invalid"?

how did you make it work?

thank you a lot

So I got a Samsung CR49 and I only can choose maximum 3840x1080 on my new Macbook Pro M1 and no 5120x1440! I'm using a new out of the box ts3 docking station. I also changed displayport to 1.2 on my samsung but still the same problem. Is this fixable or do I need tor return my macbook and stick to windows (where it works).

It’s is possible. That’s my setup.

Read through this forum and ones like it and you’ll get the info you need.

According to a recent press article Apple are aware of the problems and a fix is on the way.

Yes, I posted a message a few days ago saying the beta fixes the problem but the admins here removed my message warning me that I can't talk about beta versions of Big Sur here.

I am glad your post stayed at least so people know.

I would really help others if you exactly specify which one (really a mini M1) and OS version/revision you are already on or you upgraded on, and what Samsung 49 model/revision (regional?) exactly you are using. And to continue what port on each side and the type and quality of the cable you are using, because there are a few out in the wild and then finally what version of firmware you have on your Samsung Monitor exactly.

It is a non working non symmetric turn of the direction of causality (aka logic) to think if that if your setup is working -> all other similar but not equal setups are now working.

Helping others (and yourself) in IT challenges (hard- and software) without detailed setup information is a PITA.

Exactly describing your working septup instead of pointin to a long thread would help a lot! So give you some nudging and complete this if affordable. Thanks in advance.

"Everything (found) on the internet has to be created or written first and needs to be published at the end. If you make it impossible to find for others, you are just talking to yourself." - acsr

Can someone explain the problems with the USB-C and Thunderbolt ports?

I had a situation yesterday with my M1 Mac Mini and my Internet connection. I have 1GB of Internet yet the speed was reduced to less than 100MB. I had to reboot the M1 to gain my connection speed back.

BTW, the Internet is coming through my Thunderbolt cable which is connected to a CalDigit dock which has an ethernet connection to it.

I haven’t seen any known issues with the USB-C/Thunderbolt ports. This thread was about the issues related to the software issues with Big Sur negotiating certain resolutions over certain ports, which seems to have been substantively resolved in 11.2.

Assuming you are saying the negotiated link speed of your CalDigit to your Internet router drops to 100mbps, the most common cause of this is your network cable. You could try swapping this. If you aren’t sure if it was your link speed or not, note the color of your network connection light for the network port your connected to and then note it again the next time it drops to 100. If the colour changes then you have a network port/cable link speed issue and can try another cable... or if the issue happens enough, just try a new cable and see if it resolves it.

Since you are using the Mac Mini, when that happens, try switching your connection from your internet modem to your Mac Mini instead of your CalDigit to see if the problem persists.

If this doesn’t help, suggest you start a new thread to see if others have a similar problem.