When trying to connect the monitor via thunderbolt 3 multiple times to try to reach the ideal resolution, it may go into kernel panic. A disaster this BIG SUR! 
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After updating to 11.1 external 4K Monitor is no longer working over 1080p
- Thread starter DaveXX
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Regarding your spec your monitor should be at 144hz with DP (if not your Thunderbolt Dock is not supporting DP 1.4).
With HDMI it should have 75hz and there should be no issue with Big Sur which doesn't allow 75hz with HDMI.
So check you don't have any HDMI Compatibility Mode active with your monitor. Check that you have a High Speed HDMI Cable which supports HDMI 2.0b.
I can use full 4K60 with HDR with HDMI
I'm on my third Thunderbolt dock now—first, the CalDigit TS3Plus, then the Belkin Thunderbolt 3 Dock Pro, and now the Plugable TBT3-UDZ—and none of them have allowed my monitor to get past 75 Hz. Both the Belkin and the Plugable have been using DisplayPort 1.4, at least according to my monitor. I haven't found any settings that suggest that going to a higher refresh rate is a limitation of the monitor. Plugable does say that they don't "support" any refresh rates higher than 60 Hz, though I don't think the dock is actively preventing exceeding that.
I do see a setting on the monitor called "HDMI Compatibility Mode," but it's already disabled. This current HDMI cable is one that I dug out of a bag of old cables, so it may predate the 2.0b standard you mentioned. More concerning to me, though, is my return to using DisplayPort. Can you think of what else I can check to understand what's holding back reaching a higher refresh rate?
I do see a setting on the monitor called "HDMI Compatibility Mode," but it's already disabled. This current HDMI cable is one that I dug out of a bag of old cables, so it may predate the 2.0b standard you mentioned. More concerning to me, though, is my return to using DisplayPort. Can you think of what else I can check to understand what's holding back reaching a higher refresh rate?
Currently with Big Sur of course any Display Port connection will not work as intended. In some cases its a bit better or not (e.g. with my monitor DP 1.2 was ok but showed some weird informations and was limimted to 30hz).
But if you are at Catalina or Big Sur 11.0 (or hopefully later at a fixed 11.1+ version) it should be 144hz and if not there is no much more explanations that your dock doesn't support DP 1.4. You can try to use a USB-C to DP cable which is DP 1.4 certified to test your connection.
HDMI should not be limited in any way currently. So if there is not the full supported resolution with 75hz and 10Bit / HDR its very likely a problem with your cable.
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There's a Reddit thread that describes much the same hardware that I have, also facing this limitation.
With most of the docks you have to be carefully they really hold their promises. In your case e.g. the Calldigit even clearly specified they just support DP 1.2 so it is limited. I would always first check a direct cable connection (a cable like this is not even really expensive (about 15-20). For some reason the the TBT3-UDZ supports DP 1.4 but officially doesn't support more than 60hz in any resolution....
Regarding multiple reddit posts as well 144hz should be no problem in general.
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If you tried DP with current Big Sur 11.1 you cannot expect anything to work. As already said there is no fix yet.
Regarding HDMI its not limited to 30hz if you use the correct cable....
In general i have to say yes its is unbelievable that this problem was not identified during beta and that apple still have no fix after weeks...
But the solution with the official apple adapter i got for free from apple will let me work as before and i have no downsides - same resolution - same refresh rate - better power devlivery - hdr...
So in some cases it could be a good solution
Practically that crap update (Big Sur 11.1) was released on 14 December 2020 and since then due to the bug it is no longer possible to use usb c monitors in 4k at 60hz, I consider it very serious that Apple has not yet released any fixes. communication.
Absurd! bad management of this delicate aspect!
Absurd! bad management of this delicate aspect!
Just to avoid missunderstandings. There are no "usb-c" monitors. There is Display port over usb-c or TB. This is the reason why lg ultra fine monitors or apple monitors are not affected. They use Thunderbolt.
sorry, I meant Thunderbolt monitor, like Benq PD2720U
Apple be careful! there are people who work
Inconceivable to have released an update that makes expensive monitors unusable and in this way we are decreasing productivity.
And now almost a month goes by and Apple hasn't solved anything or released any updates yet.
Disappointed by Apple, it cannot be trusted now.
So I have a workaround that that is a pain in the ass for my duel BenQ PD2700U and I'm getting 3840x2160 at 60 refresh as well as still being able to have few peripherals plugged in such as webcam and external keyboard with Big Sur 1,1
My machine is:
2019 16" Macbook Pro
2.4 GHz 8 Core Intel I9
64GB Ram, 4 T harddrive
AMD Radeon Pro 5600M
- Unplug everything from machine
- Plug in just ONE monitor and turn on, without having downstream up stream peripheral plugged in ( it will most likely be 1080p)
- Open up display pref and option click on scaled, then click back on default display
- unplug monitor from usb-c then plug back in
- When it comes back on, then click on default for display which puts mine in 3840x2160 30
- Click on scaled and choose more space which will get it 3840x2160 60
- You can then enlarge to middle selection while still retaining 3840x2160 60
- Plug in second monitor, and nearly repeat above process, which mine is connected data port to USBc like the other one and it should be on 1080p
- Option Click scaled which should let you choose 3840x2160 this time, if not choose default.
- Regardless if you get the choice of 3840x with option click on scaled unplug the USBc cable and plug back in
- Once it's second monitor is on 3840x2160, choose scaled and more space like when doing the first monitor and it will get it from 30 refresh to 60.
- Then hook up the USB dock for your peripherals
Like I said it's a pain in the ass since I have to redo those steps if the computer goes to sleep. Hopefully that is not too confusing.
My machine is:
2019 16" Macbook Pro
2.4 GHz 8 Core Intel I9
64GB Ram, 4 T harddrive
AMD Radeon Pro 5600M
- Unplug everything from machine
- Plug in just ONE monitor and turn on, without having downstream up stream peripheral plugged in ( it will most likely be 1080p)
- Open up display pref and option click on scaled, then click back on default display
- unplug monitor from usb-c then plug back in
- When it comes back on, then click on default for display which puts mine in 3840x2160 30
- Click on scaled and choose more space which will get it 3840x2160 60
- You can then enlarge to middle selection while still retaining 3840x2160 60
- Plug in second monitor, and nearly repeat above process, which mine is connected data port to USBc like the other one and it should be on 1080p
- Option Click scaled which should let you choose 3840x2160 this time, if not choose default.
- Regardless if you get the choice of 3840x with option click on scaled unplug the USBc cable and plug back in
- Once it's second monitor is on 3840x2160, choose scaled and more space like when doing the first monitor and it will get it from 30 refresh to 60.
- Then hook up the USB dock for your peripherals
Like I said it's a pain in the ass since I have to redo those steps if the computer goes to sleep. Hopefully that is not too confusing.
BETA 2 is out, can anyone try it? Hopefully they have solved it.
www.macrumors.com
Apple Seeds Second Beta of macOS Big Sur 11.2 to Developers [Update: Public Beta Available]
Apple today seeded the second beta of an upcoming macOS Big Sur 11.2 update to developers for testing purposes, with the new beta coming a month...
www.macrumors.com
Should be very useful that some developer here give the issue to appleBETA 2 is out, can anyone try it? Hopefully they have solved it.
Apple Seeds Second Beta of macOS Big Sur 11.2 to Developers [Update: Public Beta Available]
Apple today seeded the second beta of an upcoming macOS Big Sur 11.2 update to developers for testing purposes, with the new beta coming a month...
I have 2 BenQ PD3220U. This helped me to solve the issue. I didn't have to follow the exact same steps - but clicking back and forth between scaled and default display somehow made the OS realize that the external display can be driven to 4K@60Hz.
Thanks!!
My plan is to use Amphetamine app to never make Mac go to sleep (and never disconnect it from monitors) until 11.2 is released.
Osho
Slightly off topic... Osho, how do you like the PD322OU? I have been considering this monitor, but I will likely have to figure out if it can scale text a little bigger as supported by a Mac Mini M1. But I an curious if you have been happy with this monitor. Or, in your case, you lucky stiff, with TWO such monitors
I have been very happy with the monitors.. They are excellent and work very well with Macs. Before that I had bought 2 Asus ProArt PA32UC and had to return them due to quality issues. BenQ monitors have been excellent. Until Big Sur 11.1, I could daisy chain both monitors - so with a single Thurderbolt cable, I can connect to 2 monitors and all peripherals.Slightly off topic... Osho, how do you like the PD322OU? I have been considering this monitor, but I will likely have to figure out if it can scale text a little bigger as supported by a Mac Mini M1. But I an curious if you have been happy with this monitor. Or, in your case, you lucky stiff, with TWO such monitors
BTW, I am not a photographer/videographer - I just use them for coding/productivity. So, I am not an expert on how they perform for color accurate work.
The only part I don't like is the speakers. MacBook's speakers are way better than whatever cheapo speakers are in the monitor - so I keep MacBook open and use its speakers. Also, there is no GSYNC or FreeSync - but I am not a gamer - so it doesn't matter to me.
Osho
Well.. that didn't last!
First there was this message that the issue was fixed with 11.2 latest beta, and then there are messages that the issue persists (or came back).