External monitor support

[deeddawg]

Anyone have the CalDigit Pro dock? The chart in this pages seems to imply it can use 2 external extended displays, unless I’m reading it wrong.

Apple Silicon Mac & CalDigit Dock Compatibility – CalDigit

www.caldigit.com

Looks like just a single Extended...

 

[Diode]

Anyone have the CalDigit Pro dock? The chart in this pages seems to imply it can use 2 external extended displays, unless I’m reading it wrong.

Apple Silicon Mac & CalDigit Dock Compatibility – CalDigit

www.caldigit.com

I'm not seeing that:

However, the only limitation is that the new M1-based Macs cannot support dual “Extended” displays through their Thunderbolt 3 ports. This means that when using any dock, users cannot extend their desktop over two displays, and will be limited to either dual “Mirrored” displays or 1 external display depending on the dock.

 

[Gru]

I had the same issue on my 16” pro and had to download a 3rd party app to force resolution to 5120x1440. Forgot the name of it but it’s rather popular just is escaping me right now.
Once I used the app it worked fine. I don’t have the 49” any longer so I can’t test on my m1 13” Pro

A long time ago I used SwitchResX. Don't know what happened to it.

We have almost 2021 and I'm pretty sure every new hardware supports 5120x1440. Ultra Widescreens are just way too good of an experience to ignore them.

 

[deeddawg]

Anyone using an UW-QHD monitor with their M1 yet, such as the LG 34WN80C-B or Dell U3419W or P3421W?

 

[ahlucas]

Something funky. I have 2 LG 5Ks and one will connect at 5K but the other only 4K. Never mind. Playing with SwitchResX and goofed things up.

so does it run true 5k res to a single LG UltraFine 5k? or is it forced to only 4k? (thanks!)

 

[fishkorp]

Looks like just a single Extended...

View attachment 1671014

They must’ve fixed the chart. It was all 2’s when I looked at it earlier (or I saw something mind wanted to see, lol).
Still promising that it says 2 external. So if it’s 1 mirrored and 1 extended I can maybe make that work. I also sent them an email.

 

[Jester_A]

I just got my Mac mini today and connected it to two external monitors, however only one of them are 4K 32 inch screen and the other full HD 27 inch screen. Works like a charm.

Had to buy new since my MacBook Air 2019 couldn't have both monitors working at the same time. Or I should say I could put in second monitor but if I turned it off, it wouldn't start again.

 

[cmhsam]

Anyone using an UW-QHD monitor with their M1 yet, such as the LG 34WN80C-B or Dell U3419W or P3421W?

I have the 3419W and can try later today

 

[cmhsam]

Can confirm sidecar is working on my 13" Pro M1

 

[Lammers]

I know. I was really hoping they’d change that. Guess that’s too much to ask.

Yep, would have liked that too.

 

[WigWag Workshop]

Anyone using a LG 27UL850 with an Air or a Mini?

 

[deeddawg]

I have the 3419W and can try later today

Awesome. No rush in doing so, but am curious to know since I'm considering buying one of the UW-QHD monitors as we approach Black Friday. Be nice to confirm it works before buying.

Thanks.

 

[saulinpa]

so does it run true 5k res to a single LG UltraFine 5k? or is it forced to only 4k? (thanks!)

That is a good question. Apple hides the true resolution and normally SwitchResX shows but that isn't working. I can't find the command line that will pull the clocking information. Need to find some screen time looking at high res images to compare.

 

[ahlucas]

That is a good question. Apple hides the true resolution and normally SwitchResX shows but that isn't working. I can't find the command line that will pull the clocking information. Need to find some screen time looking at high res images to compare.

you can also try out good-n-old system preferences-when you go to display settings and click the -display- tab -resolution-scaled- with -alt- pressed down when clicking, it shows true available resolutions. it should mark the 5210x2880 (if that option is even available) as active when true 5k enabled with no retina upscale (and ultra-small buttons and almost unreadable text lol).

does it charge the macbook though? and all those other functions such as thru-dock for usb-c and everything as LG 5k does normally with intel macs?

(thanks again!)

 

[Bennett_H]

Something funky. I have 2 LG 5Ks and one will connect at 5K but the other only 4K. Never mind. Playing with SwitchResX and goofed things up.

thanks for the hint! I am now able to force the resolution to 5120x1440 with SwitchResX. I hope apple will remove this issue anyway with a patch

 

[saulinpa]

MacOS lies about resolutions. Yes, it shows 5120x2880 on my M1 but that is the "back buffer" or something like that. Going through old TB2 it shows the same thing but using SwitchResX it shows actual of 3840x2160.

All functions appear working for the 5K. Camera, microphone, speakers, USB keyboard, SuperDrive. Through System Info charging says it is 85watts.

 

[Cariffo]

Heya folks,

I have read through the discussion but havent found a definitive answer.
So MBP supports only one external display, i get that.

But, can you connect 2 so that one mirrors the laptop display and the other acts like an external?

 

[cmhsam]

Anyone using an UW-QHD monitor with their M1 yet, such as the LG 34WN80C-B or Dell U3419W or P3421W?

Can confirm its working on my Dell U3419W. Monitor is plugged into my Caldigit TS3+ dock and I have the 13" M1 Pro connected to the TB dock.

 

[Delarock]

anyone tried 120 hz support?

 

[saulinpa]

Heya folks,

I have read through the discussion but havent found a definitive answer.
So MBP supports only one external display, i get that.

But, can you connect 2 so that one mirrors the laptop display and the other acts like an external?

No. A mirrored display still counts as a display.

 

[dustyblueheron]

Does anyone know if a “classic” Apple Cinema HD Display (23”, dual-link DVI) will work with the M1? I am currently using it with a 2015 MBP, using a DVI to MiniDisplayPort connection. Seems it should work with a MiniDisplayPort to USB-C adapter?

 

[Krevnik]

anyone tried 120 hz support?

After seeing some of the issues around UW and the like, I'm curious about this too.

I've got an LG 38GL950 that I use between my Mac and a Gaming PC, and I've gotten used to running 3840x1600@120Hz on the Mac side as well. That eats pretty much all the bandwidth DisplayPort 1.4 offers, and Apple doesn't actually say if they support 1.2 or 1.4 with the new machines. :|

 

[deeddawg]

Can confirm its working on my Dell U3419W. Monitor is plugged into my Caldigit TS3+ dock and I have the 13" M1 Pro connected to the TB dock.

Great news, that’s the dock I have and anticipate using. Thanks a bunch!

 

[cmhsam]

Great news, that’s the dock I have and anticipate using. Thanks a bunch!

Glad I could confirm for you and any others. I feel like I did my good deed for the MR community today

 

[fishkorp]

CalDigit had this to say in response to my question:

“Thanks for contacting us. The TS3 Plus with a M1 MacBook Pro will only have a single monitor and now mirrored monitor will be available.

On the Pro Dock, you can get a maximum of two monitors if you use a USB-C connection. This will only work when connecting to a USB-C 3.2 gen 2 port.”

I asked some follow-up clarification questions.