My guess is that you weren't really running 5K on your old MBP. Almost everything with the Intel OS reports 5K when running the LG at 4K. I would try a new TB3 cable.
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LG UltraFine 5K - Owners Thread
- Thread starter iBrooker
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In short, it should work. My first guess is the cable. If you bought it used, maybe it’s not the original? You’re sure it’s a Thunderbolt cable and not USB-C?
@petterihiisila and @saulinpa thanks so much, I think you're both right - can't believe I've been such a plank for a few weeks. I don't think it was running 5k on the old laptop either, it just appeared to say that it was in a few places. In the System Report app it says 20gbps on the old MBP so I've been looking at a 4k screen for a few weeks thinking that it was 5k!
Have just ordered 3x thunderbolt cables off Amazon (including a £65 Belkin one) and I'll test all three cables out and I'm keeping everything crossed that it is indeed the cable.
I really hope that it isn't a faulty monitor - I've heard a lot of horror stories about the input port on the back of the 5k display developing issues over time... it sure sounds like there are some reliability concerns with the monitor so I really hope it's not something like that! Thanks again, will report back when the cables have arrived!
Have just ordered 3x thunderbolt cables off Amazon (including a £65 Belkin one) and I'll test all three cables out and I'm keeping everything crossed that it is indeed the cable.
I really hope that it isn't a faulty monitor - I've heard a lot of horror stories about the input port on the back of the 5k display developing issues over time... it sure sounds like there are some reliability concerns with the monitor so I really hope it's not something like that! Thanks again, will report back when the cables have arrived!
People have had problems indeed. The worst I've heard is the TB3 connector's soldering #fail with the motherboard. Over time and presumably with accumulating push/pull/yank force, it may come off. Your problem doesn't point at that though. The symptoms are "charging works, no image", when some of the pins are disconnected. Just be gentle with it and it'll stay OK ... or at least it'll last longer.
With the Intel MBP16" 5500M I occasionally had a mismatch of pixels rows between the left and the right side of the screen. Had to lock, ESC and unlock the computer (effectively sleep and wake the screen) to fix it. Annoying but not a dealbreaker. It's not like there were any other options for 5k, and yeah, 5k is nice.
"Can't use it in 5k" ... the only context where I've heard that happen is when people are trying to use it with USB-C or otherwise a non-kosher cable. One TB3 port supports two monitors, and 5k consumes both of those at once, synchronized side by side. USB-C doesn't have enough bandwidth for that. It should show up as 40 Gbit in System Information for 5k:
With the M1 Air I've had zero issues or bugs with the 5k. I connect one cable and the 5k and more than a dozen peripherals lit up, including two more monitors (DisplayLink). In total it's a 4 display setup, as the laptop is VESA-mounted lid open. I can reliably do that during a Teams call nowadays, without expecting any hiccups. M1 Max in the mail, hope that the trend continues.
Good luck to you, hope the cable swap works out!
I've been keeping an eye on stock levels at nearby Apple Stores for the UltraFine 5K monitor, and yesterday morning one popped up as available at the store closest to me (which is unfortunately still an hour away). So I purchased online and picked up in store.
I got it home, hooked it up to my M1 Mac mini, and fired it up. I'm coming from an ASUS ProArt PA279CV which has been an amazing display running at a scaled setting (1440), and right off the bat I could tell that the resolution on the 5K is noticeably better. However, I am seeing a pink cast on the screen, especially on the left side.
Attached are two pictures, one of the ProArt and one of the 5K. Am I being too picky here? Is this normal? For $1,200 I feel like I should get more consistent quality, but perhaps I'm wrong. Any input is appreciated.
ASUS ProArt PA279CV
LG UltraFine 5K
I got it home, hooked it up to my M1 Mac mini, and fired it up. I'm coming from an ASUS ProArt PA279CV which has been an amazing display running at a scaled setting (1440), and right off the bat I could tell that the resolution on the 5K is noticeably better. However, I am seeing a pink cast on the screen, especially on the left side.
Attached are two pictures, one of the ProArt and one of the 5K. Am I being too picky here? Is this normal? For $1,200 I feel like I should get more consistent quality, but perhaps I'm wrong. Any input is appreciated.
ASUS ProArt PA279CV
LG UltraFine 5K
Just updating here to say that I was indeed an idiot and using a USB-C cable and not a Thunderbolt 3 cable and now the issue is totally resolved.
Turns out that Intel Macs do not make it clear that the Ultrafine 5k monitor is only running at 4k when connected with just a usb-c cable.
Also adding to the complexity is that I was under the impression that the 5k monitor I was using was an early model which only supported display over Thunderbolt, but turns out it's a newer one that supports USB-C and Thunderbolt, with USB-C being limited to just 4k. Happy that it's fixed anyways with just a cheap new cable
Turns out that Intel Macs do not make it clear that the Ultrafine 5k monitor is only running at 4k when connected with just a usb-c cable.
Also adding to the complexity is that I was under the impression that the 5k monitor I was using was an early model which only supported display over Thunderbolt, but turns out it's a newer one that supports USB-C and Thunderbolt, with USB-C being limited to just 4k. Happy that it's fixed anyways with just a cheap new cable
The Apple stores in Georgia seem to be getting them sporadically, at least lately. The issue is the closest store, which is still over an hour away, doesn't have one (since I just bought it), and the online Apple store won't have any to ship for a few months. I suppose I could always order a second one for pickup and return this one when I pick it up, but it's difficult enough to find the time these days.
I just installed the monitor on my VESA desk mount, so for now I am going to give it a shot. There is an extended return period, so if nothing else I will keep an eye on local stock and decide after Christmas.
I've the latest 27MD5KL-B which supports both USB-C and TB inputs but requires me to change cables if I switch between my 2018 iPad Pro and Mac mini.
Would changing to either the really expensive Apple Pro Cable or Plugable TB4 cable circumvent that? I just want a single input cable that lets me swap between both my iPad Pro and Mac Mini without the need to change out the input cable.
Apple Pro Cable: https://www.amazon.com/Apple-MWP32AM-A-Thunderbolt-3-Pro-Cable/dp/B08BNDHZZL
Plugable TB 4 Cable: https://www.amazon.com/Plugable-Thunderbolt-Certified-Charging-Compatible/dp/B09C1LV8XC
Would changing to either the really expensive Apple Pro Cable or Plugable TB4 cable circumvent that? I just want a single input cable that lets me swap between both my iPad Pro and Mac Mini without the need to change out the input cable.
Apple Pro Cable: https://www.amazon.com/Apple-MWP32AM-A-Thunderbolt-3-Pro-Cable/dp/B08BNDHZZL
Plugable TB 4 Cable: https://www.amazon.com/Plugable-Thunderbolt-Certified-Charging-Compatible/dp/B09C1LV8XC
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I have this weird issue with the LG 5K (27md5kl-b) connected to a MacBook Pro (16-inch, 2019)
1. It all started with the original TB3 cable dying (it was providing charge, but the display stayed black).
2. Bought a new cable and everything seemed find for a few days
3. Then *IT* started, the display would randomly flicker for 1-2 seconds, seaming at random
* it’s not a physical connection issue, messing with the cable has no correlation with the flicker
* it’s not an WIFI interference issue (I moved the display around the house… say issue)
* it’s not a load issue (fresh boot, idle… flicker doesn’t care)
* it’s not a cable issue: I bought a second Apple branded TB3 cable… same thing
4. The weirdest part if that (based on some limited testing) it works perfectly find with a 2016 15” MacBook Pro, so maybe it’s a MacBook problem, but it seems to be working just fine in every other way.
---
Other “clues” I gathered:
* Sometimes when I connect the display there are 2 vertical lines on the screen where the image is offset by 2 pixels, this get's fixed by replugging the cable and it's not always in the same place.
* The flickering is not consistent (sometimes it’s every 10 seconds, sometimes every 30 min)
* Tried every port and every configuration I could think of (clamshell mode, laptop mode)
* I removed every thing around that could possible cause interference (Bluetooth mouse, phone, headphones)
* The external SSD plugged into the back of the display does not disconnect then screen flickers)
* I did reset the PRAM and SMC
* Flicker still happens with MacBook booted in “Single User Mode”
* The flicker doesn’t happen when connected using a USB-C cable (but running in 4K)
---
Any idea what could cause this, and is there a solution that doesn’t involve replacing the MacBook? (I’d rather stay on Intel for a bit longer and I don’t wanna purchase another Intel Mac)
Thanks
1. It all started with the original TB3 cable dying (it was providing charge, but the display stayed black).
2. Bought a new cable and everything seemed find for a few days
3. Then *IT* started, the display would randomly flicker for 1-2 seconds, seaming at random
* it’s not a physical connection issue, messing with the cable has no correlation with the flicker
* it’s not an WIFI interference issue (I moved the display around the house… say issue)
* it’s not a load issue (fresh boot, idle… flicker doesn’t care)
* it’s not a cable issue: I bought a second Apple branded TB3 cable… same thing
4. The weirdest part if that (based on some limited testing) it works perfectly find with a 2016 15” MacBook Pro, so maybe it’s a MacBook problem, but it seems to be working just fine in every other way.
---
Other “clues” I gathered:
* Sometimes when I connect the display there are 2 vertical lines on the screen where the image is offset by 2 pixels, this get's fixed by replugging the cable and it's not always in the same place.
* The flickering is not consistent (sometimes it’s every 10 seconds, sometimes every 30 min)
* Tried every port and every configuration I could think of (clamshell mode, laptop mode)
* I removed every thing around that could possible cause interference (Bluetooth mouse, phone, headphones)
* The external SSD plugged into the back of the display does not disconnect then screen flickers)
* I did reset the PRAM and SMC
* Flicker still happens with MacBook booted in “Single User Mode”
* The flicker doesn’t happen when connected using a USB-C cable (but running in 4K)
---
Any idea what could cause this, and is there a solution that doesn’t involve replacing the MacBook? (I’d rather stay on Intel for a bit longer and I don’t wanna purchase another Intel Mac)
Thanks
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[mention]dan.fraticiu [/mention] it seems, unfortunately, the 2019 MBP is the issue as the problem doesn't show with the old 2016 MBP. And probably not the tb3 port but the controller, as it shows when connected at any port.
However, I will say try to test first the display with a third mac somehow, to confirm.
However, I will say try to test first the display with a third mac somehow, to confirm.
Thanks, that's what I was afraid of. I wander if there is a way to test the thunderbolt controller independently of the display?
Hi! I bought the Ultrafine 5K two weeks ago and it works pretty well. I have a weird issue though, and I find nothing similar on internet so far. There's a folder named 27MD5KL that keeps popping in my Downloads folder. Each time that I delete it, it reappears a few minutes after. The folder itself is empty. It's not a big deal, but a little annoying and I don't know where that comes from. The only thing I downloaded related to the monitor is the LG Screen Manager, but I see nothing in the settings that could explain the existence of this folder. Can anybody help me with that?
I believe that is because you downloaded the LG App from the appstore. I assume it was setting the folders up in case there were files for a firmware download. I recently downloaded the app to check for a firmware update, and the same folders were present. I deleted the app, then the folders and they don't re-appear.
Has anyone had issues connecting a new M1 24" iMac with the 5k Ultrafine? Any pictures? I'm curious to see how they line up side by side. I'm currently using a M1 Mac mini with my Ultrafine, but am considering upgrading to an iMac to get more screen space. Thanks.
I'm using a 5k Ultrafine with an M1 24" imac. It seems to be working just fine - no problems at all. I also use (a different) 5k Ultrafine with an i9 imac. They are both (fingers-crossed) working fine at the moment.
Hi, thanks for the response. With the adjustable stand on the LG, are you able to get the screens fairly level and lined up? Any chance you can share a photo?
I've had LG 5K Ultra fine for 4 years now and everything works fine! now I have connected it to the new Macbook M1 Max
Now you have jinxed it. I predict your display will fail by the end of the week!