Use a USB-C cable with the Siig adapter, not the Thunderbolt cable, that fixed my flashing issue. If you aren't on 11.0.1 and are on a newer version of Big Sur you will most likely be missing key resolutions that SwitchResX can't currently restore, but you will be able too see the adapter works and it's an Apple bug.
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m1 mac mini + dual ultrafine
- Thread starter phine
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This is a nightmare. Pretty ridiculous of Apple. Purchased 2 LG 5K Ultrafine's a couple months ago. Just purchased the M1 Mac mini and can ONLY USE ONE SCREEN. Can someone find a solution for this?
I purchased two the the LG Ultrafine 4K displays but no adapter for the thunderbolt 3/USB C to HDMI seems to work. Does your LG 4K only have the thunderbolt 3 and USB C ports? If so, how are you connecting? I have purchased both the SIIG adapter you link above, as well as, the Belkin USB C to HDMI sold on Apple's website. Neither works and now Apple tech support says this particular HDMI port has to connect HDMI to HDMI, i.e. without an adapter. Any help would be appreciated!!
I just purchased the M1 mini and it does not support two LG UF 4K monitors despite Apple's website at least implying that it does. The Siig adapter did not work. Apple suggested I buy the Belkin adapter it sells. Didn't work either. Now I was just told the only way the HDMI port will work if the monitor has an HDMI port, i.e. no adapter.
I'm currently using two LG UF 4K monitors with an M1 Mac mini that I rolled back to 11.0.1 using DFU mode without any issues. So it DID work with the Siig adapter just fine, seems like there are still just bugs to fix (hopefully).
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Did you make sure to use a USB-C cable and NOT a Thunderbolt cable? That was my first issue with the Siig adapter, but there will be missing resolutions once you get the display to come on.
@ Simcoxjt -> How were you able to get both monitors running @ 2304x1296? My second (Connected to the Siig) jumps right over the resolution you are using. I'm stuck with either 1280*720 (super blurry) or 3840*2160 (so small the content is impossible to see). My primary is connected @ 1920*1080, but I have a wide range of options to choose from, working just fine.
I'm on the 11.3 Public Beta and running 2x LG 4k Ultra Fine Displays, same setup as you I believe, on an M1 Mac mini
I'm on the 11.3 Public Beta and running 2x LG 4k Ultra Fine Displays, same setup as you I believe, on an M1 Mac mini
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I only got it working once I found a way to roll back to 11.0.1, it seems display resolutions for some HDMI and USB-C connected displays is still an issue. It was broken by 11.1, not fixed in 11.2, and looking like it won't be fixed in 11.3. The issue isn't even isolated to those using M1 macs or those using adapters. It just seems that 4k or >4k monitors that don't use Thunderbolt are likely to be missing resolutions or their native resolution isn't detected properly.
Just wanted to chime in and say I've got the same issue, Mac mini M1, Siig adapter plugged into Mac, Moshi Displayport to USBC going from Siig to Thunderbolt port on Ultrafine 4k and the only resolutions I have are what you see in the screenshot. I've also got a Belkin Thunderbolt Pro Dock and was hoping I could plug the Moshi into the DisplayPort and run that to the Ultrafine with the help of DisplayLink Manager but I couldn't get that to work at all.
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11.3 Beta 7, still no change to available resolutions. Anyone able to engineer a workaround for this yet?
Super odd that the second display, via this setup can easily display 3840 x 2180 all the way down to 1024 x 768, but is missing so many of the key ones in the middle. I wonder where in the software this disconnect lives and if this is even on the radar/roadmap to be addressed since the situation seems unique to these "Siig USB-C to HDMI adapter" setups.
Super odd that the second display, via this setup can easily display 3840 x 2180 all the way down to 1024 x 768, but is missing so many of the key ones in the middle. I wonder where in the software this disconnect lives and if this is even on the radar/roadmap to be addressed since the situation seems unique to these "Siig USB-C to HDMI adapter" setups.
Has anyone had success with 24” LG Ultrafine 4K in a daisychain setup from M1 Mac mini?
I really need a placeholder desktop for home work and tempted to pickup the m1 mini, but dual HiDPI displays is a must.
I did a bunch of conversion setups using my 22” UltraFine 4K on my old 2015 MBP. After lots of trial an error with different adapters I found the best were from either StarTech or DeLock.
I know Club3D has an active HDMI>dP 1.2 adapter that runs at 4096x2160 @ 60hz. Since (in theory) you have a proper 1.2 dP signal using the StarTech bidirectional dP > Usb-C cable should work fine on the 22” or 24” ultrafine 4K displays.
StarTech also has a newer dP 1.4 adapter cable that might work on the 5K ultrafine, however I believe the m1 HDMI is locked down at 3840x2160.
https://www.club-3d.com/en/detail/2491/hdmit_to_displayportt_4k60hz_m-f_active_adapter/
https://www.startech.com/en-us/audio-video-products/cdp2dp1mbd
I really need a placeholder desktop for home work and tempted to pickup the m1 mini, but dual HiDPI displays is a must.
I did a bunch of conversion setups using my 22” UltraFine 4K on my old 2015 MBP. After lots of trial an error with different adapters I found the best were from either StarTech or DeLock.
I know Club3D has an active HDMI>dP 1.2 adapter that runs at 4096x2160 @ 60hz. Since (in theory) you have a proper 1.2 dP signal using the StarTech bidirectional dP > Usb-C cable should work fine on the 22” or 24” ultrafine 4K displays.
StarTech also has a newer dP 1.4 adapter cable that might work on the 5K ultrafine, however I believe the m1 HDMI is locked down at 3840x2160.
https://www.club-3d.com/en/detail/2491/hdmit_to_displayportt_4k60hz_m-f_active_adapter/
https://www.startech.com/en-us/audio-video-products/cdp2dp1mbd
For those of you using an M1 mini, and having trouble getting hidpi resolutions on a 24" LG Ultrafine 4K using the Siig USB-C to HDMI adapter, (along with a 24" or 27" LG Thunderbolt Display), you may want to try putting the M1 to sleep and then waking it up. Or lock the screens and at the login screen press cancel, and once the screens go dark, wake up the M1. The hidpi resolutions should then show up for the display using the Siig adapter. Works for me, Ymmv.
Two observations to report.
1. It seems the adaptor will send the signal to my monitor with or without the additional USB-A power connected. Odd behavior, unsure why this is.
2.SIIG now indicates on their web site that they adaptor is not compatible with the LG Ultrafine Displays. Thats new news... so maybe they were getting a lot of complaints?
1. It seems the adaptor will send the signal to my monitor with or without the additional USB-A power connected. Odd behavior, unsure why this is.
2.SIIG now indicates on their web site that they adaptor is not compatible with the LG Ultrafine Displays. Thats new news... so maybe they were getting a lot of complaints?
Hoping something gets released today to fix this or a new Mac Mini with the capability to run the ultrafine.
The only way to run the 27" UltraFine (doesn't matter if it's the old or new model) at 5K 60Hz 10bpc is dual-link DP 1.2 SST encapsulated in Thunderbolt 3.
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So this is my setup : Mac mini M1 16GB 1TB + dual LG Ultrafine 24'' for Mac 24MD4KL-B.
It was quite difficult to make them run together in HiDPI mode.
Right here I am emulating 218 dpi with a working resolution of 2304 x 1296 (virtual resolution is 4608 x 2592) on both monitors
Everything is super sharp (texts and images)
So what to I need ?
An active adaptor from Club3D : HDMI to USB-C. Around 50€ in Europe.
Then set as primary monitor in preference plane the Ultrafine connected to Thunderbolt 3 with the Thunderbolt 3 cable included with the LG.
Last set as secondary monitor the one connected to HDMI to USB-C adaptor with the USB-C cable included with the LG
Like that preference plane will give access to HiDPI (scaled mode) for both monitors. And it will remember it.
Then enjoy dual 4K 24" with your Mac mini M1.
By the way Mac mini M1 is way better than iMac M1. the mini is constantly 10% faster and it runs cool and totally silently, even under load. Whereas iMac M1 will run hot with the fans kicking in loudly under load.
So I send the iMac away, keeping the mini
Hey, can you explain more about your setup?
I have similar setup to yours, M1 Mac mini with dual 24" Ultrafine 4k. First one is connected to the Thunderbolt 3 port and works without any problems.
Second monitor is connected to the HDMI port using the Club 3D CAC-1332 adapter.
Club3D HDMI™ to USB C 4K60Hz Active Adapter Male/Female, CAC-1332
The Club 3D CAC-1332 is an HDMI to USB C Active adapter that allows you to transfer an HDMI signal to a display supported by USB C DisplayPort. This product supports resolutions up to 4096 x 2160 @ 60Hz. This adapter is unidirectional and only works display. It is equipped with a USB micro USB fo...
www.amazon.de
But I can't use any HiDPI resolution for the second monitor. 3840 x 2160 is available in 60hz but UI is of course tiny.
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Is that 3840x2160 HiDPI actually pixel-doubled, or does it just say HiDPI because it's at the monitor's max resolution? I thought M1 Macs couldn't do pixel doubling for resolutions above 3008x1692.
Unfortunately, this still won't work for the 5K monitors.
Any solutions out there yet?