LG UltraFine 5K - Owners Thread

[anthony13]

Yes, that is correct. I haven't seen it in a while, but I used to see both halves of the screen (left and right) come on at very slightly different times when I was plugging in the monitor to my laptop. I think this is a limitation of Thunderbolt 3, if I recall correctly. I know that DisplayPort 1.2 doesn't support 5K and behaves the same way.

Thanks! I have noticed that my iMac turns off True Tone on one side first when shutting down. That makes sense.

 

[joevt]

New to this thread, but I've always wondered; I think I read that 5K iMac's from apple actually use two drivers to get to 5K. This is one of the reasons they supposedly stopped supporting target display mode? Regardless, do LG 5K ultra fine monitors have to do similar processing?

I don't know the reason why Apple stopped supporting Target Display Mode. For Thunderbolt Target Display Mode, there was some software component involved - I supposed they could have made the software work with dual tiled displays with some extra work. You can tell the iMac and LG displays are tiled by looking at the listed DisplayPort connections in the AGDCDiagnose command output. For M1 Macs, the script at https://gist.github.com/joevt/e862b0088ef58b9144877d01401bcee8 should tell you if the current display is tiled or not (uses two DisplayPort connections).

I think this is a limitation of Thunderbolt 3, if I recall correctly. I know that DisplayPort 1.2 doesn't support 5K and behaves the same way.

The LG UltraFine 5K displays were initially created with Alpine Ridge Thunderbolt controllers which are limited to two DisplayPort 1.2 connections (allows 5K60 10bpc). The new LG UltraFine 5K displays use the Titan Ridge Thunderbolt controller which supports DisplayPort 1.4, but DisplayPort 1.4 allows only 50% more bandwidth than DisplayPort 1.2, so it can only support 5K60 at 8 bpc (but the LG UltraFine 5K doesn't accept DisplayPort 1.4 input anyway, nor does it accept a pixel clock higher than ≈600 MHz). Dual DisplayPort 1.2 is 33% more bandwidth than DisplayPort 1.4 so it can do 5K60 at 10bpc.

A single DisplayPort 1.2 connection can support 5K30Hz (one person got up to 39Hz 8bpc on the LG UltraFine 5K).

There exist 5K displays that can take DisplayPort 1.4 as input. With one of those displays, DisplayPort 1.2 could do up to maybe 45Hz 8bpc. In Windows, 5K60Hz is possible with DisplayPort 1.2 using 6bpc. macOS doesn't support 6bpc, but it can do chroma sub sampling (up to 4:2:2 with DisplayPort 1.2 and 4:2:0 with DisplayPort 1.4).

 

[jimthing]

I don't know the reason why Apple stopped supporting Target Display Mode. For Thunderbolt Target Display Mode, there was some software component involved - I supposed they could have made the software work with dual tiled displays with some extra work. You can tell the iMac and LG displays are tiled by looking at the listed DisplayPort connections in the AGDCDiagnose command output. For M1 Macs, the script at https://gist.github.com/joevt/e862b0088ef58b9144877d01401bcee8 should tell you if the current display is tiled or not (uses two DisplayPort connections).


The LG UltraFine 5K displays were initially created with Alpine Ridge Thunderbolt controllers which are limited to two DisplayPort 1.2 connections (allows 5K60 10bpc). The new LG UltraFine 5K displays use the Titan Ridge Thunderbolt controller which supports DisplayPort 1.4, but DisplayPort 1.4 allows only 50% more bandwidth than DisplayPort 1.2, so it can only support 5K60 at 8 bpc (but the LG UltraFine 5K doesn't accept DisplayPort 1.4 input anyway, nor does it accept a pixel clock higher than ≈600 MHz). Dual DisplayPort 1.2 is 33% more bandwidth than DisplayPort 1.4 so it can do 5K60 at 10bpc.

A single DisplayPort 1.2 connection can support 5K30Hz (one person got up to 39Hz 8bpc on the LG UltraFine 5K).

There exist 5K displays that can take DisplayPort 1.4 as input. With one of those displays, DisplayPort 1.2 could do up to maybe 45Hz 8bpc. In Windows, 5K60Hz is possible with DisplayPort 1.2 using 6bpc. macOS doesn't support 6bpc, but it can do chroma sub sampling (up to 4:2:2 with DisplayPort 1.2 and 4:2:0 with DisplayPort 1.4).

Sorry, like your previous answers, while knowledgeable, they're very confusing. Try re-reading it, and see if you can write it better for the layman to understan the points you're trying to make. A list of specs isn't that, unfortunately. ?

 

[joevt]

Sorry, like your previous answers, while knowledgeable, they're very confusing. Try re-reading it, and see if you can write it better for the layman to understan the points you're trying to make. A list of specs isn't that, unfortunately. ?

anthony13 read some info that said 5K iMacs use two drivers to get 5K. I explained that the 5K iMacs and LG displays are tiled displays (meaning they have two 2560x2880 tiles each using a separate DisplayPort 1.2 signal over the Thunderbolt cable). I also explained how to discover the tiled info or the connection info that shows two connections are being used.

anthony13 asked why Apple stopped support Target Display Mode. I speculated that Apple didn't have to stop supporting it - they just have to update the code to support the tiled displays.

kerplunknet said some stuff about Thunderbolt 3 limits and that DisplayPort 1.2 doesn't support 5K. I explained that there are ways for DisplayPort 1.2 to support 5K (using tiled display, or lower the refresh rate, or lower the number of bits required for each pixel). I explained that the tile display method is superior to using DisplayPort 1.4 since DisplayPort 1.4 has less bandwidth than dual DisplayPort 1.2. Also, DisplayPort 1.2 is compatible with more Macs and older Macs.

I think I used perfectly good English. If a reader has trouble with any of the words, then they can search for them in google or wikipedia or ask specific questions about them here.

 

[kevinq]

Hello. I have an LG 22MD4KA-B monitor and I'm trying to update the firmware. The "LG Screen Manager" application doesn't display the monitor software version. Here's a screenshot: https://prnt.sc/vwz4b9 and Settings: https://prnt.sc/vwz4y6

I'm using the latest version of the LG Screen Manager app from App Store (v. 2.79). The LG Screen Manager recognizes the monitor as "LG UltaFine" but I can't identify or update the software/firmware.

Troubleshooting: I've restarted computer (MacBook Pro 13" 2018), tried different USB C ports on computer and monitor, uninstalled/reinstalled LG Screen Manager app. Tried the same on MacBook Air 2018, tried on Catalina and Big Sur...

Can anyone help me find the firmware file that I can upload to the LG Screen Manager app, or tell me how to contact LG to get the firmware.

Thanks, Daniel

For anyone getting this error: "LG Screen Manager is not supported with connected monitor"

I contact LG support and this is simply because starting from High Sierra (version 10.13), it is not necessary to use the LG Screen Manager software to update the monitor anymore, it is embedded in macOS updated themselves.

 

[jimthing]

For anyone getting this error: "LG Screen Manager is not supported with connected monitor"

I contact LG support and this is simply because starting from High Sierra (version 10.13), it is not necessary to use the LG Screen Manager software to update the monitor anymore, it is embedded in macOS updated themselves.

1. How do you know it's recently been updated?
2. Where does one see the version?

 

[dukee101]

Has anyone purchased an LG 5K recently (from the 12/2020 manufacturing batch) and experienced a weird vertical banding / "tiger stripes" issue? It's hard to notice if directly looking at the screen, but the moment you shift your head around, you'll notice these wavy bands/stripes.

It's hard to capture, but it's pretty much the issue raised by @ralphthemagi in 2019. I've gone through two units already and they both exhibit this issue. If you use dead-pixel-check, it's most pronounced in the red and green colors. Any feedback would be appreciated!

 

[djsegler]

Hi friends -

Trying to repair a 27MD5KA (broken thunderbolt connector), and I’ve noticed a couple diodes missing or damaged (D109 and D110 around the thunderbolt connector.

Does anyone know what parts I should replace them with? I’m guessing they are for ESD protection.

I don’t have schematics so any help would be much appreciated.

Thanks!

 

[chrizel]

Has anyone purchased an LG 5K recently (from the 12/2020 manufacturing batch) and experienced a weird vertical banding / "tiger stripes" issue? It's hard to notice if directly looking at the screen, but the moment you shift your head around, you'll notice these wavy bands/stripes.

It's hard to capture, but it's pretty much the issue raised by @ralphthemagi in 2019. I've gone through two units already and they both exhibit this issue. If you use dead-pixel-check, it's most pronounced in the red and green colors. Any feedback would be appreciated!

I have an LG 5K from the 12/2020 batch. I don't notice this issue with the dead-pixel-check, but maybe it is subjective and my eyes are too dumb to notice this effect. ? I do notice some backlight bleeding, but still in the adequate range for an LCD as far as I can tell.

Still very satisfied with this display after two weeks coming from a 1440p Dell monitor.

 

[dukee101]

I have an LG 5K from the 12/2020 batch. I don't notice this issue with the dead-pixel-check, but maybe it is subjective and my eyes are too dumb to notice this effect. ? I do notice some backlight bleeding, but still in the adequate range for an LCD as far as I can tell.

Still very satisfied with this display after two weeks coming from a 1440p Dell monitor.

Thank you for chiming in @chrizel! Glad that you got a solid display. I've seen a number of these LG 5Ks and they do have backlight bleeding as you say, but I agree that it's within an acceptable range. I'm not picky about those things, but if there's something truly defective, I'm going to call it out, especially for a $1,300 monitor!

I love the LG 5K truth be told -- there's just no monitor like it if you're a Mac user. I just wish LG's quality control was better. Clearly the panels getting sent to Apple for iMacs have more stringent QC standards.

 

[Mr Screech]

Received my Ultrafine 5k today and hooked it up to a MBP M1, with another 27" monitor through a displaylink adapter. Whenever I reboot, the Ultrafine loses it's orientation and the entire arrangement is reset. Is there any setting or utility which helps remembering the arrangement?

My previous setup had a 27" directly connected to my Caldigit TS3+ and it never had this problem.

//this might have been asked before, but a search didn't show anything in this thread.

 

[kevinq]

1. How do you know it's recently been updated?
2. Where does one see the version?

No idea! If you contact them, please let us know what they tell you.


Little update, I'll keep the LG 5K but it's not perfect. Often, it doesn't wake up, or the screen stays black. I lose so much time when that happens...
Just switched to an Apple Thunderbolt cable, let's see.
Glad to report that the screen has auto-brightness enabled and it works without using the Macbook's sensor (MBP is always closed), that's a great plus.

 

[Splex]

Hi All,

I purchased a refurbished LG ultrafine 5k (27MD5KL) recently manufactured in Nov 2020. As normally observed in other posts, it has uniformity issues, which I can accept to some extent since no better choice in the market meeting the same standard HiDPI as MBP. The thing that I can't stand is it shows a warmer or pink tone, which is rather obvious when viewing sites with a white background. Does anyone know if it is possible to resolve the colour hue issues with colour calibration (recommended tools?), or it is actually a defective unit that I have to request for a swap?

Thanks!

 

[pacificblue]

A bit of a warning:

After updating my M1 Mac mini to the developer beta of macOS 11.3 Beta (20E5196f), my UltraFine 5k developed a strange issue (pic related).
Some of the pixels near the right edge of the display are going in and out of alignment in a vertical band, maybe 50 pixels wide. I doubt this is the same pixel alignment issue that has been discussed here, as that was about static alignment issue and on my display the misalignment is constantly moving like this.

It's definitely a software issue though — the same display with the same cable works just fine on another Mac with a stable version of macOS 11.2.

View attachment 1737994

As of beta 4 of macOS Big Sur 11.3, this issue is fixed.

 

[kerplunknet]

‎

 

[Splex]

I use the X-Rite i1Display Studio. I like their software too.

Are you observing the difference or improvements after calibration? I'm currently planning to give the X-rite i1 display studio a try.

 

[kerplunknet]

‎

 

[Splex]

It made a noticeable difference for me. I calibrate all of my computer monitors, including laptop screen. There is a before/after in the software.

Choose the D65 option, 2.2 gamma, and your brightness should be about 120 cd/m2.

Thanks.

Did you follow the same steps to calibrate the laptop and your monitors or merely get the statics of the mac's built-in display and calibrate other monitors based on that? I'm asking cause I want to know how to enable consistent visual quality across different screens.

 

[WP31]

I def have the same issue, always assumed it was just a color calibration/screen difference that I would have to live with. I've tried to make a LG5k and LG 34" Ultrawide the same color for a couple years and never found an easy way to do it. Am interested in any advice anyone can provide. Will look at X-Rite i1Display Studio. Thx!

 

[kerplunknet]

‎

 

[Splex]

Same settings for any computer display.

6500K color temperature, 2.2 gamma, 120 cd/m2 is the most common standard.

Which correction file (suppose you use displayCAL for calibration) do you select? Thankfully, I got my x-rite i1display pro plus today and have calibrated both of my MacBook pro 15 as well as ultrafine 5k. The overall colour tone of the two panels looks somewhat close but the colour is a bit washed out or the colour being less saturated.

 

[Splex]

Same settings for any computer display.

6500K color temperature, 2.2 gamma, 120 cd/m2 is the most common standard.

Here is the uniformity test of my ultrafine 5k. Could you please let me know about yours?

Appreciate anyone's advice: is this monitor acceptable or a defective unit (one area of the panel does not meet nominal tolerance) that I have to return/swap.

Thanks!

 

[dukee101]

Has anyone purchased an LG 5K recently (from the 12/2020 manufacturing batch) and experienced a weird vertical banding / "tiger stripes" issue? It's hard to notice if directly looking at the screen, but the moment you shift your head around, you'll notice these wavy bands/stripes.

It's hard to capture, but it's pretty much the issue raised by @ralphthemagi in 2019. I've gone through two units already and they both exhibit this issue. If you use dead-pixel-check, it's most pronounced in the red and green colors. Any feedback would be appreciated!

Following up here: I exchanged my LG 5K for a unit from the February 2021 manufacturing batch and it does not exhibit this issue. If you bring home one of these and it has the problem I originally described, do not accept that "it's just the way it is". It is absolutely a QC issue from the factory with certain batches. All this said, love this monitor. Nothing as sharp as this monitor on the market right now.

 

[AeroUK]

How do you know the date of manufacture?

 

[dukee101]

How do you know the date of manufacture?

Good question! The date of manufacture is embedded into the monitor's serial number as the first three digits. The SN can be found either on the outside packaging/box, or under the monitor's bezel, on the right side when facing the monitor directly in the front. For example, the serial number 012NTDV2F986 should be interpreted as: "0" = 2020; "12" = December. In another example, an S/N starting with 103* should be interpreted as: "1" = 2021; "03" = March.