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LG UltraFine 5K - Owners Thread

Curious if anybody here is running a dual LG 5k UltraFine setup with a 14" or 16" M1 Pro / Max AND happen to be running the Ventura Beta. I am running this setup in the office, and have been experiencing horrible networking issues that I have narrowed down to running two of this. I have an open ticket against the Ventura Beta with Apple on this but wanted to see if anybody else is seeing this.

Basically, Safari, Chrome, Slack etc all lose reliable connectivity and are nearly unusable with both displays hooked up. This is connected via Wi-Fi and a Uni USB-C Gigabit Ethernet adapter.

Both displays are 27MD5KL.. I have verified in the System Profiler that both are connected at 40Gbps, I don't even have the resolutions cranked up on them to full 5k.

Based on reading this thread I swapped one of the displays' thunderbolt cable for a USB-C to bring it down to 4k to see if that would help and unfortunately it didn't. Next I will try a Thunderbolt 3 adapter <-- Thunderbolt 2 Cable --> Thunderbolt 3 adapter. I'm just getting a little desperate trying to find a work around for this until its addressed.

If I unplug one of the displays everything works fantastic again.
 
wait are you not directly hardwired for both displays? So running both through an adapter
 
dadodaa said:
View attachment 2039641Hello everyone,

I am about to order an UltraFine 4K monitor and I would like to know if it is possible to detach the base from the stand. I am not talking about the stand, but only the base that you put on a desk.

I had done it on my Dell monitor to screw it on like on the picture below.

Thanks in advance.
Click to expand...
I don't think you can, the neck of the stand is built into the base. It is height adjustable by the weight of the monitor.
 
My new work laptop is an 2021 (M1 Pro) 14-inch MacBook Pro. I tried to connect my 27-inch LG UltraFine 5K monitor, and the screen is black. I hear a USB connection sound play when I plug it in, however, indicating the laptop is being charged and getting power.

At some point, I plugged in the Mac power adapter and replugged the LG UltraFine 5K and it turned on after a few minutes randomly.

Am I missing something? Anyone have the trick to make this work?
 
Not familiar with the issue, so here are just the usual steps: Reboot laptop, disconnect display from power for a couple of seconds, try a different cable, try plugging in a different port. Defective cables do happen.
 
It's pretty much plug in and go. Are you using the supplied thunderbolt cable and does the monitor show up in the display settings? Is the firmware up-to-date on the monitor?
 
Thanks for responding so quickly, @Chris60549 and @Zigman. My gut is that it's the cable. This is the cable I'm using: https://www.amazon.com/gp/product/B07R43LPCX/ref=ppx_yo_dt_b_search_asin_title

This cable worked perfectly with my old 2016 15-inch Intel MacBook Pro and my 2020 13-inch M1 MacBook Air. The 2021 14-inch M1 MacBook Pro has Thunderbolt 4 ports and the other two machines had Thunderbolt 3 ports. I am going to go to the Apple Store tomorrow morning and buy a Thunderbolt 4 cable to see if that fixes things.

Oddly enough, I was working on a Lenovo 32-inch 4K monitor with its default USB-C cable and it worked.

To answer your questions, no, the monitor does not show up in the settings. Firmware is up to date.

I truly appreciate the tips/recommendations.
 
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I'm between getting the LG 5K or a 27" 4K monitor (such as the Dell U2723QE), but the big things holding me back from this are 1) the huge/ugly bezels) and 2) the lack of ports. I'm looking for a monitor to use between both my work and personal Macbooks, and having to move the cable back and forth between them (compared to just switching inputs) sounds like a pain.
 
Hello,

I just bought a 27" LG Ultrafine 5K screen (ref: 27MD5KL) for my Macbook Pro 15" retina mid-2014.
Plugged-in via Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 adapter + TB2 cable.
After 1 hour of unsuccessful attempts, the screen remains desperately black. My MBP's screen does show the LG Ultrafine 5K in the monitors though, and the LG screen manager utility also "sees" the monitor properly connected. Annoying... Tested with my son's Dell laptop (in thunderbolt 4) and it works perfectly (if plugged into the mains).
Apple announced on this link (archive) that my MBP was compatible, in 4K of course : https://support.apple.com/en-us/HT207448
Many MBP users, and many articles confirmed this compatibility, but now there's is a contradictory news in the apple site which announces 4K compatibility FROM 2015 macbook pros (!): https://support.apple.com/en-us/HT210205

1/ Was the mid-2014 MBP actually compatible before, and not now (new LG 5K firmware?)
2/ Do I need a more recent version of MacOS on my MBP? (I am in 10.12.6, which seems to be OK in my first links).
3/ And finally is there another way to make it work (via HDMI + adapters?) even in a lower resolution?

I was planning to buy a new Macbook pro, but much later, and I would like it to work with the current one.
Very disappointed with this experience with this LG screen, it is sold as "display for mac" and it is impossible to operate, except with Windows (!) with it works the first time in TB4 (which at least allowed me to realize that this screen has a very beautiful display quality...)

Thanks in advance for your tips and feedback, and sorry for my english.
 
You definitely have the 27MD5KL and not the 27MD5KA? the earlier model only supported thunderbolt 3 only. The later one supports 4K displayport over USB-C I believe.
 
Yes I confirm that it is indeed the 27MDK5L. It was produced in March 2022 according to the label on the packaging box.
 
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bluemonk said:
Yes I confirm that it is indeed the 27MDK5L. It was produced in March 2022 according to the label on the packaging box.
Click to expand...
Maybe you can try using the provided USB-C cable to see if it works on USB mode? If not maybe try swapping out the Tb cable?
 
The problem is I have no USB-C on my macbook. I use a TB2/TB2 cable, plugged in the adapter TB2 to TB3 (USB-C), plugged in the screen. I cannot use the provided USB-C cable, unless I use for example my son's Dell laptop, which has USB-C (TB4).
 
bluemonk said:
The problem is I have no USB-C on my macbook. I use a TB2/TB2 cable, plugged in the adapter TB2 to TB3 (USB-C), plugged in the screen. I cannot use the provided USB-C cable, unless I use for example my son's Dell laptop, which has USB-C (TB4).
Click to expand...
You can get USB-C if you connect a Thunderbolt 3 dock.

But before doing that, see what SwitchResX says about the display.

Can you use USB devices connected to the display?

Does the display appear in the Thunderbolt tab of System Information.app? Also the PCI tab and the USB tab?
 
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Thanks a lot to all for your help.
I just called LG hotline, but they have no solution since the screen works with Windows...

Yes I can access to my iPhone plugged in a USB-C connection to the display.
I just installed SwitchResX and the LG Ultrafine appears in it.
The LG display appears in the Thunderbolt tab of the system information, also appears in the USB 3.1 tab (with its camera, audio), but I am not sure it appears in the PCI tab. Here's what I see in PCI (in french sorry) :

pci8086,15f0 :

Type : Contrôleur d’hôte USB eXtensible
Gestionnaire installé : Oui
Compatible avec les tunnels : Oui
Pause possible : Oui
MSI : Oui
Bus : PCI
Logement : Thunderbolt@195,0,0
Identifiant du fournisseur : 0x8086
Identifiant du périphérique : 0x15f0
Identifiant du fournisseur du sous-système : 0x1854
Identifiant du sous-système : 0x0285
Identifiant de révision : 0x0006
Largeur du câble : x4
Vitesse de la liaison : 2.5 GT/s

Thank you.
 
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Do you think updating MacOS to a newer version could solve the problem ?
(my MacOS version is 10.12.6)
 
bluemonk said:
Thanks a lot to all for your help.
I just called LG hotline, but they have no solution since the screen works with Windows...

Yes I can access to my iPhone plugged in a USB-C connection to the display.
I just installed SwitchResX and the LG Ultrafine appears in it.
The LG display appears in the Thunderbolt tab of the system information, also appears in the USB 3.1 tab (with its camera, audio), but I am not sure it appears in the PCI tab. Here's what I see in PCI (in french sorry) :

pci8086,15f0 :

Type : Contrôleur d’hôte USB eXtensible
Gestionnaire installé : Oui
Compatible avec les tunnels : Oui
Pause possible : Oui
MSI : Oui
Bus : PCI
Logement : Thunderbolt@195,0,0
Identifiant du fournisseur : 0x8086
Identifiant du périphérique : 0x15f0
Identifiant du fournisseur du sous-système : 0x1854
Identifiant du sous-système : 0x0285
Identifiant de révision : 0x0006
Largeur du câble : x4
Vitesse de la liaison : 2.5 GT/s
Click to expand...
pci8086,15f0 might be the USB controller in the LG UltraFine 5K. https://pci-ids.ucw.cz/read/PC/8086/15f0
It should match the USB bus that the LG display's camera and audio connect to.

What modes are listed in SwitchResX? Did you try them all?

SwitchResX has a Menus option. In the Menubar Extra column, there's a checkbox for Enable/Disable display. Enable that. Then see if there's a disable/enable option in the SwitchResX Menubar Extra (right side of the menubar - the SwitchResX Daemon needs to be running to see the menu). Disable the display. Then reenable it.

Did you try pulling the power of the LG?

Is there a firmware update for the display?

I don't know if a newer macOS would help but it shouldn't hurt to try. Maybe you can install it to a new partition or an external USB drive if you want to keep the current macOS version.
 
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Try a different TB2-TB3 adapter, e.g. the white Apple one. (I would try to do this at their store if you are close enough.) However, running this display at 4K is a total waste. The blurriness will hurt your eyes.
 
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joevt said:
pci8086,15f0 might be the USB controller in the LG UltraFine 5K. https://pci-ids.ucw.cz/read/PC/8086/15f0
It should match the USB bus that the LG display's camera and audio connect to.

What modes are listed in SwitchResX? Did you try them all?

SwitchResX has a Menus option. In the Menubar Extra column, there's a checkbox for Enable/Disable display. Enable that. Then see if there's a disable/enable option in the SwitchResX Menubar Extra (right side of the menubar - the SwitchResX Daemon needs to be running to see the menu). Disable the display. Then reenable it.

Did you try pulling the power of the LG?

Is there a firmware update for the display?

I don't know if a newer macOS would help but it shouldn't hurt to try. Maybe you can install it to a new partition or an external USB drive if you want to keep the current macOS version.
Click to expand...
Thank you for your answer.
Some people had the exact same problem here : https://discussions.apple.com/thread/251205996
But I am not sure the answer about USB-C/TB3 is right...

Anyway, here's a screenshot of SwitchResX, the optimised resolutions are in bold characters. I tried all the resolutions but none did work.
I did activate the Daemon, and could get the Extra menu, I disabled then enabled again the LG display, but nothing happened. I tried pulling the power of the LG several times. The LG firmware is the latest.
I just called Apple Care, we tried several things, the hotliner thinks it's a software limitation issue, my MBP and the LG cannot "talk together" although all the hardware seems to be OK.
He told me to try install MacOS Mojave (10.14.6)
So I made a time machine save, and I will now try to install Mojave on my main partition (because I don't know how to do it another way, I am pretty newbie to all of these things...)
I will let you know if it works.
Thank you again for your help.
 

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Chris60549 said:
Try a different TB2-TB3 adapter, e.g. the white Apple one. (I would try to do this at their store if you are close enough.) However, running this display at 4K is a total waste. The blurriness will hurt your eyes.
Click to expand...
I have the original (white) TB2/TB3 adapter, and the original Apple TB2 cable too. I don't have any other adapter, and it's so expensive (almost 100$ for both) !
First I'll try to update my MacOS, and hope it will solve the problem.
I know the LG screen won't be so great in 4K, but I plan to buy a new M1 MBP in less than 3 months, and would like to use my 2014 MBP with the LG until this time. Thanks for your help.
 
bluemonk said:
Some people had the exact same problem here : https://discussions.apple.com/thread/251205996
But I am not sure the answer about USB-C/TB3 is right...
Click to expand...
That guy doesn't know what he's talking about. The Apple Thunderbolt 3 to Thunderbolt 2 Adapter works in both directions. We already know it works for you because the display appears in the Thunderbolt tab in System Information.app, and also in the USB tab and the PCI tab and the Graphics/Display tab.

You might have better luck connecting the display as USB-C instead of Thunderbolt. A Belkin Charge and Sync cable would be best for that method. However, USB 3.0 devices connected to the display will connect only as USB 2.0 in that case.
 
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joevt said:
That guy doesn't know what he's talking about. The Apple Thunderbolt 3 to Thunderbolt 2 Adapter works in both directions. We already know it works for you because the display appears in the Thunderbolt tab in System Information.app, and also in the USB tab and the PCI tab and the Graphics/Display tab.

You might have better luck connecting the display as USB-C instead of Thunderbolt. A Belkin Charge and Sync cable would be best for that method. However, USB 3.0 devices connected to the display will connect only as USB 2.0 in that case.
Click to expand...
Yes it seemed to me that that guy did not completely master the subject...
What kind of Belkin cable is this ? Do you have a link if possible? Thank you.

(I am updating Mojave. Last hope for it to work!)
 
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