M1 Mac Mini and Thunderbolt Display

The M1 Mac mini can't run two Thunderbolt displays, but the LG UltraFine 4K Display does not have to be used as a Thunderbolt display. It comes with two cables: one Thunderbolt 3, one USB-C non-Thunderbolt. When using the non-Thunderbolt cable it can be connected to a non-Thunderbolt USB-C port.

LG UltraFine 4K Display - Apple

"Video, data, and power over a single Thunderbolt 3 (USB-C) cable (included) or USB-C cable (included)

Connection: Thunderbolt 3–enabled Mac, USB-C–enabled Mac or iPad Pro"

Using the non-Thunderbolt USB-C cable, it should work from the computer's HDMI port with a HDMI to USB-C converter.

I tried hooking up two monitors using DisplayPort over UCB-C while not using the built in HDMI port on my M1 Mac Mini and I could only get one monitor to work a time which seems to confirm the Apple spec that you can connect one monitor to the USB-C ports and one to the HDMI port. I can see reading the spec and wondering if it means that it is a limitation or a suggested setup of two monitors but it appears to be a limitation. That being said I have not tried daisy chaining Thunderbolt displays but it seems unlikely to me that it would be any different.

I have two Apple 27" Thunderbolt Displays connected to my 2020 MacBook Air, Display 1 is plugged into the MBA via a Thunderbolt to USB-C (TB4) adapter and the second 27" TB Display is plugged into the first. As you would expect, that works fine.

Today, I received my M1 MacBook Air, 16GB/512GB. Same configuration as above but only 1 display works. However, hard drives plugged into the display work, USB and FIreWire 400. Haven't tried a TB hard drive yet. Ethernet is also working. From what I've read, the only thing that MIGHT work, is getting a USB-C dock, and and adapter to convert the 2nd TB display to HDMI. That should/might work, but I'm sure none of the USB/FW/EtherNet/TB ports on the 2nd display will work. It would be really interesting to hear Apple's justification for what seems like a backward step. I've been running the 2 TB displays off several MBAs for probably 6 or 7 years. Now the latest and greatest MBA doesn't support this. Don't really want to buy a new display. Hopefully, a solution comes along soon that will allow this to work and all the ports to work as always.

You can run more displays using DisplayLink software, but it's not using the GPU, so they will have limited performance.

https://www.macrumors.com/2020/11/24/m1-macs-able-to-run-six-external-displays/

It is indeed very disappointing, I've been using two Apple displays for close to 15 years, with various MacBook Pros and MacBook Airs. I'm already missing the extra space. But I'll live with it. Looked at getting a new larger display, maybe a curved one, but with no camera, limited ports compared to the TB Display, it's even more frustrating. I've got ethernet, a few older FireWire 800 drives that I still use, etc. all plugged into the TB Display and it all still works with the M1 MBA. Maybe the next version will support 2 TB displays.

So the number of monitors seems to be hard-wired into the Mac minis. Of course, since the HDMI port is more limited than , your expansion options via the TB Display is limited (if that was part of your intent). You could try a Dock at macsales.com, among many others. eGPU-s are also not [yet] compatible.

There is further information via the link provided.

https://support.apple.com/guide/mac-mini/connect-a-display-apd8e4fbbb97/mac

From Mac mini Essentials:

The Thunderbolt 3 (USB-C) ports  and the HDMI 2.0 port both support video output, so you can connect an external display, a projector, or an HDTV.

• For Mac mini with Apple M1 chip, you can connect one external display up to 6K using a Thunderbolt 3 (USB-C) port, and one external display up to 4K using the HDMI 2.0 port.
• For other Mac mini models, the Thunderbolt 3 (USB-C) ports on your Mac mini are managed by two controllers—one for the two ports on the left, and one for the two ports on the right. You can connect one 5K display using a Thunderbolt 3 (USB-C) port, or up to three 4K displays using two Thunderbolt 3 (USB-C) ports and the HDMI 2.0 port.

My Mac Mini M1 arrived today. I have two 27" Apple Thunderbolt Displays mounted on my desk. I purchased two Apple Thunderbolt 2 to 3 adapters, however, only 1 display will work. I understand the 2nd monitor has to be hooked to HDMI. Is there any way to convert the Thunderbolt 2 to HDMI so that I can use both of these displays with the new Mac? I can hook them both up to my 2014 MacBook Pro just fine.

I have bought the Mac Mini M1 and I have a Cinema Display and a Thunderbolt Display. I have them hooked up just fine thanx to this thread. To sum it up:

Apple Thunderbolt Display --> Apple Thunderbolt Display to USB-C adapter --> Mac Mini M1 = 2560 x 1440 @ 60.00Hz 👍🏻

Apple Cinema Display --> Mini DP female to DP male adapter by Cable Matters --> Delock Adapter HDMI-A male to DisplayPort female 4K 60 Hz (hint, the sell directly from the website, just click Buy Now) ps, this one is active and need usb power --> Mac Mini M1 = 2560 x 1440 @ 60.00Hz 👍🏻

While waiting for the Cable Matters cable I found another solution myself since I didn't have the patience to wait. So this is a alternative solution that also worked 100%.

Apple Cinema Display --> Mini DP double female --> Mini DP to DP cable --> Delock Adapter HDMI-A male to DisplayPort female 4K 60 Hz

I think the solution that made the differnce was the Delock cable. It didn't work until I hooked up the usb cable that was in the box (didn't know what it was for). Now everything works 100% all the time.

Good luck!

Christian Schneider

//Wonderbird - Webbyrå Stockholm

At the bottom of that link it says:

1. Actual display support varies by computer specifications. Supported Intel-based Apple Mac models and Thunderbolt 4 PCs support two displays over a Thunderbolt port. Apple M1 Mac models support a single display over a Thunderbolt port.

It appears that unless there is some kind of firmware change, the M1 will only support 1 external Thunderbolt monitor

Hello everyone,

I had a 27 inch thunderbolt from 2017 which i wanted to be my main screen for my new setup with M1 chip. I recently purchased a macbook air M1 and thunderbolt 3 to thunderbolt 2 from apple. To my surprise, M1 air did not detect the thunderbolt display at all.

Wherein i have been using the same display with an old macbook Air late 2013 via the thunderbolt port.

To check if the thunderbolt 3 to thunderbolt 2 is working fine or not, i connected it to a 2020 Macbook pro intel and the thunderbolt display is identified and all the ports work.

Tried my level best to connect the display to m1 macbook air but failed. I tried the following:

• Updated the os to the latest, now on 11.2.1
• Rebooted couple of times plugged in and out.
• Created a new admin user to see if that works.
• Also tried by installing third party multi display adapter softwares but nothing worked out.

Please suggest me what can i do that my setup comes to life.

It seems you are out of luck with 2 thunderbolt displays, on the apple website the mac mini has this video output:

Video Support

• Simultaneously supports up to two displays:
• One display with up to 6K resolution at 60Hz connected via Thunderbolt and one display with up to 4K resolution at 60Hz connected via HDMI 2.0
• Thunderbolt 3 digital video output supports
• Native DisplayPort output over USB‑C
• Thunderbolt 2, DVI, and VGA output supported using adapters (sold separately)
• HDMI 2.0 display video output
• Support for one display with up to 4K resolution at 60Hz
• DVI output using HDMI to DVI Adapter (sold separately)

So can't have 2 monitors connected to 2 thunderbolts.

I just got the m1 mini, and the Apple Thunderbolt to USB-C (thunderbolt 3) adapter and while it works, there is a flickering artifact on the display in the top row of pixels. I hope to get a hold of another Thunderbolt display to test with to see if it's specific to this particular unit.

I am in the same boat. I also have an older DVI input with HDMI monitor that will not work with M1 Mac Mini. So the set up looks nice with two landscape 27" Apple Thunderbolt Displays and a portrait 27" Dell monitor, but only one 27" Apple Thunderbolt Display with Thunderbolt 2 to 3 adapter will work.