LG UltraFine 5K - Owners Thread

[eldho]

Also, just noticed that he USB hub is dead, does nothing, no power delivery, no data, is that bad news ? hardware issue ?

Does the USB hub itself need mains power? Some do, some don't. I assume this is a completely separate issue from the monitor.

 

[After2k]

I mean the usb hub in the back of the screen, the usb ports of the LG ultrafine 5K

 

[eldho]

I mean the usb hub in the back of the screen, the usb ports of the LG ultrafine 5K

That does sound like a 'bad news hardware issue'. Please excuse me for asking as I do not know the impact of this but I assume that you have the cable from your computer plugged into the correct port at the back. I am simply asking this because I really don't know what else to check and have no idea as to the impact if the cable was in one of the other ports.

 

[After2k]

Yes, the thunderbolt cable is supplying power to my laptop, it is the stock TB cable plugged to the right port on both ends

 

[eldho]

I don't regard myself as an expert but to me it sounds as if you indeed have a hardware problem. At the moment with all that we have been through this is most likely a connector problem either in the cable or the monitor, or even possibly your laptop. Do you know anyone else who could lend you a cable or try your monitor with their own laptop and cable? The monitor itself is a heavy thing to lug around but if you got it from a local store you could challenge them to see if they can get it to work. My condolences and all the best for getting this sorted out - very frustrating stuff when you just want the ..... thing to work!

 

[etc]

Yes, the thunderbolt cable is supplying power to my laptop, it is the stock TB cable plugged to the right port on both ends

It's very clear that USB connectivity does not work in your case, only DisplayPort signal. I suppose you need to check if you allowed any accessories to connect to your MBP

Allow accessories to connect to Mac

If you have a Mac laptop with Apple silicon, you must approve new USB and Thunderbolt devices and SD cards before they can communicate with your Mac.

support.apple.com

 

[After2k]

Nope, im already allowing all connections, it was a hardware issue, LG diagnosed it and it's gonna get repair/replaced.

 

[upstream8721]

I got the 2019 27MD5KLB-B I ordered from eBay that was listed as "Open Box". There is a small area in the bottom right corner of the display where I think there may be a small piece of dust or debris under the glass. It is about the size of a "." character. Any way to fix this?

 

[ralphthemagi]

I just bought a "new/open box" LB-B which I should get in next week. I plan to take some precautions to minimize wear on the USB-C port. Aside from not using PD over the monitor's thunderbolt port, is it worth avoiding the use of an active thunderbolt cable as this might introduce more heat? I would be interested in what type of USB-C extensions you are using. That should help reduce wear on the port, but I don't want to get a cheap cable that might makes things worse by introducing more heat.

This will be my first thunderbolt 3 device, and I'm learning the different cable specifications. If I use a short (passive) male-to-female usb-c extension cable that is rated for 40Gbps along with the 2m active cable that ships with the monitor, will that give me the best chance of reducing both heat and mechanical wear?

I use the cable the display comes with on all my displays. I don't use hubs, just plug directly into the MacBook or iPad. For all my other premium cable needs I almost exclusively use Cable Matters, with a few Anker cables or adapters here and there. Monoprice for a few USB adapters and ethernet cables. Always had good luck with Cable Matters. They replaced an HDMI cable that went bad for me years after purchase, no questions asked.

There is little rhyme or reason to how/when these displays fail. My OLDEST display (2019) has outlasted two newer ones. Having opened them up and tried to have them repaired… it's just a bad design. Not designed to last. What's amazing is that it's never been fixed. The LB-B is the business model that comes with a 3-year warranty vs 1-year for the L-B (consumer model). That's the best you can really do.

I just had a 2016 MacBook Pro that had one of the USB-C connectors die on me. This machine was otherwise flawless, but right on the edge of being obsolete, so I took it into the Apple Store to get repaired figuring this was my last shot to have the work done by Apple. For all the nonsense and poor repairability that Apple does, the USB-C connectors on this model has the USB-C connectors on easily replaceable daughter boards. The part was $14. The labor was $99. They repaired it in less than a week. Good design decision IMO. USB-C PD is both really cool and terrible. USB-C ports need adequate thermal design, and even then you must plan to make the connector itself serviceable because they WILL fail eventually. At the bare minimum the connector needs to be laid on the PCB away from other plastic components so you can easily remove it and replace it without irreparably damaging anything else.

 

[ralphthemagi]

This is very intriguing. But why would LG only sell an updated model in the UK?

There is somebody in this forum, that claims to have a model manufactured in January of this year that is the P.

I just purchased one that arrived last week manufactured in May of this year.

In the US. It is not a P version, but it is noticeably, obviously, superior to the 2019 I had as soon as I turned it on the first time it was obvious.

It does still have quite a bit of backlight bleed though.

If I had to guess, and I do because there is no information available, the P version is probably for UK/EU compliance.

 

[PaulD-UK]

Quote: @ralphthemagi "If I use a short (passive) male-to-female usb-c extension cable that is rated for 40Gbps along with the 2m active cable that ships with the monitor..."

'Rated for' is a data rating.
'Certified for' 8K video is another matter.
Buying Thunderbolt 4 cabling means it should be certified (by Intel...)
USB4 might be certified - with the 20/40 logo, or might just be 'compatible with'.

I don't know if any 'Certified for' manufacturers make the sort of extension cable you want.
I suspect only 'compatible with' cables exist? Which is probably not the same thing ay all...

Nearly all the monitor problems reported here seem to stem from inappropriate cabling.

 

[kerplunknet]

‎

 

[tjhcom]

I have two LG 5k displays including one newer LG 27MD5KL-B (the other is an older model). I have them both successfully working with no issues, connected to two of the thunderbolt ports on my new M2 Mac Studio. I understand, from Apple, that the HDMI port on the Studio supports a 5k display. However, I can't determine if this is possible with this particular 5k display (the LG 27MD5KL-B). I would like to free-up a thunderbolt port if possible.

Specifically, the USB-C to HDMI cables currently available that support 8k are unidirectional (USB-C --> HDMI). If I were to use an 8k HDMI cable, I would need an adapter to convert the HDMI signal to the appropriate USB-C for the back of the monitor. Does such an adapter exist? I realize I can get it working at a lower resolution but want it to be 5k (same resolution as the other monitor). All suggestions welcome. Thanks.

 

[eksu]

The Gen 1 5K display doesn’t take USB-C in and the Gen 2 accepts USB-C at max 3840x2160 and scales it. At these pixel densities sometimes it can be hard to tell you aren’t getting the full image so check in system profiler.

 

[joevt]

The Gen 1 5K display doesn’t take USB-C in and the Gen 2 accepts USB-C at max 3840x2160 and scales it. At these pixel densities sometimes it can be hard to tell you aren’t getting the full image so check in system profiler.

macOS doesn't tell you when you are scaling 4K up to 5K. You need to look at the timing info to be sure (SwitchResX or AllRez).

5K60 on the LG UltraFine 5K requires a Thunderbolt connection that supports two DisplayPort HBR2 connections. The LG UltraFine 5K can also accept a single HBR2 connection for 5K up to 39 Hz (with a custom timing).

 

[tjhcom]

macOS doesn't tell you when you are scaling 4K up to 5K. You need to look at the timing info to be sure (SwitchResX or AllRez).

5K60 on the LG UltraFine 5K requires a Thunderbolt connection that supports two DisplayPort HBR2 connections. The LG UltraFine 5K can also accept a single HBR2 connection for 5K up to 39 Hz (with a custom timing).

In the system information panel, both monitors show resolution of 5760x3240. I do have them both set at 2880x1620 at 60Hz. I have to looked at the timing information and will look into this (as I currently don't know how to check this).

I am looking for a solution using the HDMI port on my Studio, for this (5k thunderbolt-only) monitor, that produces the same results. Does this currently exist? Thanks.

 

[joevt]

In the system information panel, both monitors show resolution of 5760x3240. I do have them both set at 2880x1620 at 60Hz. I have to looked at the timing information and will look into this (as I currently don't know how to check this).

I am looking for a solution using the HDMI port on my Studio, for this (5k thunderbolt-only) monitor, that produces the same results. Does this currently exist? Thanks.

5760x3240 and 2880x1620 are probably scaled modes. SwitchResX will show which modes are scaled.

In SwitchResX, double click the current resolution in the Current Resolutions list for the display. That will show the timing info (pixel clock, etc.). It also shows the resolution of scaled modes so you can see if it's scaled to 5K or 4K.

A Thunderbolt-only display like the original LG UltraFine 5K can only be connected to Thunderbolt. Why would you want to use the HDMI port?

If you want to connect an LG UltraFine 5K to the HDMI port then it would need to be the newer version of the LG UltraFine 5K using a HDMI to USB-C adapter such as the Club-3d CAC-1336. Older HDMI to DisplayPort adapters are limited to 4K output. You would need to use a custom timing of 39Hz to get 5K. I don't know if the LG works well with the CAC-1336.

To get 5K60, you would need to use a Thunderbolt add-in card. Connect two DisplayPort inputs from the Studio. You can use a Thunderbolt port to get the two DisplayPort outputs. I don't know of any way to get two DisplayPort outputs from an HDMI port. It would take an adapter that costs hundreds of dollars and probably doesn't exist yet. It would be less expensive to get a new display.

 

[tjhcom]

5760x3240 and 2880x1620 are probably scaled modes. SwitchResX will show which modes are scaled.

In SwitchResX, double click the current resolution in the Current Resolutions list for the display. That will show the timing info (pixel clock, etc.). It also shows the resolution of scaled modes so you can see if it's scaled to 5K or 4K.

A Thunderbolt-only display like the original LG UltraFine 5K can only be connected to Thunderbolt. Why would you want to use the HDMI port?

If you want to connect an LG UltraFine 5K to the HDMI port then it would need to be the newer version of the LG UltraFine 5K using a HDMI to USB-C adapter such as the Club-3d CAC-1336. Older HDMI to DisplayPort adapters are limited to 4K output. You would need to use a custom timing of 39Hz to get 5K. I don't know if the LG works well with the CAC-1336.

To get 5K60, you would need to use a Thunderbolt add-in card. Connect two DisplayPort inputs from the Studio. You can use a Thunderbolt port to get the two DisplayPort outputs. I don't know of any way to get two DisplayPort outputs from an HDMI port. It would take an adapter that costs hundreds of dollars and probably doesn't exist yet. It would be less expensive to get a new display.

joevt, thank you very much. This is very helpful. I downloaded SwitchResX and studied the settings.

As context, I have two LG monitors, one is an older (2018) LG 27MD5KB-B and one is a new LG 27MD5KL-B. They are both connected via thunderbolt cables to 2 of the 4 ports on the back of the new M2 Studio Max. They are both set at 2880x1620 which SwitchResX shows as scaled. If I select (in the Apple System Settings Display section) 5120x2880, both monitors will accept this resolution and SwitchResX shows this resolution is not scaled.

To answer your question, I am simply trying to free up a thunderbolt port if possible, by making use of the HDMI port instead if I can get the same resolution. I would rather not purchase another monitor to accomplish this (i.e., a monitor that will directly accept an HDMI cable at this resolution). I want a solution that works just like my current setup, in which both monitors appear exactly the same (I am using them as one extended desktop).

What I don't know is this: since I'm only using 2880x1620 (and don't plan to switch to 5120x2880), do I even need to be concerned about the maximum resolution of any available solution (assuming I can get it to at least 2880x1620)? Does having a monitor that is capable of 5120x2880 but scaled to 2880x1620 provide additional benefits (sharper rendering of the lower resolution, for example)? If not, then I only need a solution that can permit me to get 2880x1620. One other consideration: I would prefer to manage this right from the System Settings Display panel vs. a third party software (i.e., with custom settings etc.).

In summary, I want to drive one of the LG monitors (don't care which one, but assume it would be the new one) with the HDMI port on the Studio (in order to free up a thunderbolt port), if there is no downside to doing this. Looking for any suggested solution to try out but assume, if it exists, it would consist of an adequate HDMI cable and HDMI-> USB-C/Thunderbolt adapter.

All questions and suggestions welcome. Thanks again.

 

[joevt]

What I don't know is this: since I'm only using 2880x1620 (and don't plan to switch to 5120x2880), do I even need to be concerned about the maximum resolution of any available solution (assuming I can get it to at least 2880x1620)? Does having a monitor that is capable of 5120x2880 but scaled to 2880x1620 provide additional benefits (sharper rendering of the lower resolution, for example)? If not, then I only need a solution that can permit me to get 2880x1620. One other consideration: I would prefer to manage this right from the System Settings Display panel vs. a third party software (i.e., with custom settings etc.).

Yes, you need to be concerned. Check SwitchResX again. 2880x1620 is probably a scaled HiDPI mode. HiDPI mode means it's using twice as many pixels vertically and horizontally (4 times as many pixels total) to render graphical objects such as text (compared to non retina displays). SwitchResX should show that scaled pixels are 5760x3240 and that is scaled down by the GPU to the active pixels which is 5120x2880.

You can use the Displays preferences panel in System Preferences.app and it will tell you if a mode is not retina (low resolution) but it won't tell you if it's scaled what the active pixels are.

You can use SwitchResX to select a 2880x1620 mode that is not scaled and is not HiDPI to see how crappy it is.

In summary, I want to drive one of the LG monitors (don't care which one, but assume it would be the new one) with the HDMI port on the Studio (in order to free up a thunderbolt port), if there is no downside to doing this. Looking for any suggested solution to try out but assume, if it exists, it would consist of an adequate HDMI cable and HDMI-> USB-C/Thunderbolt adapter.

For the newer LG UltraFine 5K display that supports USB-C input, the Club-3d CAC-1336 might get you 4K60 or 5K39 or it might not work. I don't trust displays that don't have buttons to work properly. The USB-C output of the CAC-1336 might have issues with some USB-C adapters (it's meant to work with USB-C cables only) but I was able to get around that by putting a CalDigit Element Hub between the USB-C adapter and the CAC-1336. https://insights.club-3d.com/thread/cac-1336-operation/

If you use something like the Club-3d CAC-1335, then you can use a DisplayPort + USB to USB-C cable.
https://forums.macrumors.com/threads/alternative-to-the-belkin-vr-cable.2378619/

You can try finding examples of people attempting to use a Thunderbolt 3 add-in card in a Thunderbolt PCIe expansion chassis to convert DisplayPort output to Thunderbolt. I suppose you could take DisplayPort output from a CAC-1335 into the Thunderbolt add-in card and maybe it might get video output to the older Thunderbolt only LG UltraFine 5K but it would still be limited to 4K60 or 5K39 if it works at all.
https://egpu.io/akitio-node-duo-review-two-slots-endless-possibilities/

5K60 requires two DisplayPort 1.2 signals from Thunderbolt. I suppose a video wall processor could take a signal and split it into two halves but I don't know of any that can take 5120x2880 as input and output two 2560x2880 signals. Someone could take an FPGA that costs thousands of dollars and make such an adapter (actually I don't know how much it costs - its one of those things where if you have to ask then you probably can't afford it).

 

[ralphthemagi]

The Gen 1 5K display doesn’t take USB-C in and the Gen 2 accepts USB-C at max 3840x2160 and scales it. At these pixel densities sometimes it can be hard to tell you aren’t getting the full image so check in system profiler.

It's very easy to tell on the 5K Ultrafine if it's scaled or not. It's blurry, particularly around text. Maybe with a smaller screen you might not be able to notice, but at 27" it's very obvious.

 

[etc]

Hi there! I'm looking for a cheap TB3 dock compatible with Intel Mac to pair it with UltraFine 5K. Mainly to prevent TB3 connector from wearing because of power delivery through it. I tried connecting 87W apple power adapter that comes with Intel MBP, but UltraFine provides more power (94W), so the system does not switch charging port.

Why Intel specifically? Because a used HP Elite TB3 Dock I just bought for 25$ works great with my M1 Max MBP even if it's labeled "Unsupported" - same as Intel Mac does in sys info. But on Intel it's really "unsupported" - no DP signal, no USB - charge only.

I found solutions like TB3 enabler, but they are outdated and don't work anymore. It seems patching Ventura's or Sonoma's kexts is very difficult now.

Currently I use a short USB-C cable with 60W PD and MBP then switched to apple power adapter. But I want 5K60, not 5K through 4K framebuffer

So, are there any cheap options? HP Thunderbolt Dock G2 maybe? I also see a used StarTech TB3 dock on the market, but no power supply in the box and it provides only 15W for charging (not a big problem, but I'd like to get rid of apple adapter). I'm not quite sure that it's supported too.

 

[LotsOfBees]

im trying to update my 27MD5KA through Lg screen manager in Macos Ventura but gets stuck at 20% and then its cancelled. Anyone have similar problem? I tried a bunch times and updated to Sonoma, still not working.

 

[eldho]

im trying to update my 27MD5KA through Lg screen manager in Macos Ventura but gets stuck at 20% and then its cancelled. Anyone have similar problem?

Mine is a 27MD5KL so it may not be relevant but I did not have that problem and my version is 3.14,2.23...etc so it has updated to a later version than what you have. I am a bit neurotic about not touching anything while it is updating. All the best with getting yours sorted.

 

[LotsOfBees]

i figured it out, on apple silicon macs you need to install rosetta or LG Screen Manager will fail after downloading the firmware binary, no idea why.

After installing rosetta the update is working!!

 

[ralphthemagi]

Hi there! I'm looking for a cheap TB3 dock compatible with Intel Mac to pair it with UltraFine 5K. Mainly to prevent TB3 connector from wearing because of power delivery through it. I tried connecting 87W apple power adapter that comes with Intel MBP, but UltraFine provides more power (94W), so the system does not switch charging port.

Why Intel specifically? Because a used HP Elite TB3 Dock I just bought for 25$ works great with my M1 Max MBP even if it's labeled "Unsupported" - same as Intel Mac does in sys info. But on Intel it's really "unsupported" - no DP signal, no USB - charge only.

I found solutions like TB3 enabler, but they are outdated and don't work anymore. It seems patching Ventura's or Sonoma's kexts is very difficult now.

Currently I use a short USB-C cable with 60W PD and MBP then switched to apple power adapter. But I want 5K60, not 5K through 4K framebuffer

So, are there any cheap options? HP Thunderbolt Dock G2 maybe? I also see a used StarTech TB3 dock on the market, but no power supply in the box and it provides only 15W for charging (not a big problem, but I'd like to get rid of apple adapter). I'm not quite sure that it's supported too.

Easiest solution is just to buy a 100W GaN charger.