LG UltraFine 5K - Issues/bugs

Successful Sorcerer

macrumors member
Nov 23, 2019
74
14
I actually still have my iMac 5k and set it side by side with my lg 5k displaying different colors at full screen. I had to turn down my iMac 5k 5 levels to match the brightness. My problem is that sometimes my living room gets too bright and i dont have control over it so i need to push the brightness of my displays
So there's probably something wrong with your LG 5K.
 

defn

macrumors regular
Apr 25, 2015
103
126
My 16" MacBook Pro wouldn't wake my 5K screen upon waking from sleep. Can confirm that resetting PRAM/NVRAM helped fix this.

Image retention seems to be getting worse, I'm not sure if it's because I've started using Dark Mode.
 

Nomad110

macrumors regular
Jun 16, 2012
119
26
My 16" MacBook Pro wouldn't wake my 5K screen upon waking from sleep. Can confirm that resetting PRAM/NVRAM helped fix this.

Image retention seems to be getting worse, I'm not sure if it's because I've started using Dark Mode.
I am seeing the same thing. We have several of these 5K LG UltraFines in the office. Some are showing image retention of the the Apple Logo in the upper left hand corner. We are in the process of switching everything to Pro Display XDR...just too many issues with these displays.
 

Macdude2010

macrumors 65816
Mar 17, 2010
1,143
188
The Apple Store
I am seeing the same thing. We have several of these 5K LG UltraFines in the office. Some are showing image retention of the the Apple Logo in the upper left hand corner. We are in the process of switching everything to Pro Display XDR...just too many issues with these displays.
Are these the old 27 inch ultrafines or the refresh that happened over the summer?
 
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Nomad110

macrumors regular
Jun 16, 2012
119
26
Are these the old 27 inch ultrafines or the refresh that happened over the summer?
These are the first gen UltraFine 5Ks.
- - Post merged: - -

Also I can add that, zapping the NVRAM or PRAM did not fix the sleep/wake issue for me on the 16" MBP. The display will not come back on once the display turns off. It's really annoying. I have to unplug the display thunderbolt cable and replug for it to come back online.
 

palter

macrumors member
Feb 17, 2006
59
30
Boston, MA
PRAM reset fixed the problem. Thanks for the suggestion.
Well, since updating to macOS Catalina 10.15.2, I find that I frequently have to unplug/plug my 5K in order to get it to wakeup when I wake up my MBP. Also, it gets into the state that requires a PRAM reset every couple weeks. Sigh.
 
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randomshelf11

macrumors newbie
Dec 31, 2019
2
1
I have a 2.4 GHz i9, 5500M 8GB, 16" MacBook Pro.

I frequently experience at least one these issues when it is connected to my UltraFine 5K:
  • no brightness control for monitor;
  • USB devices connected to monitor don't register;
  • monitor's webcam doesn't turn on.
These issues sort themselves out if I unplug it then plug it back in again multiple times until all of the issues are no longer present, but it is still a pain. Locking the screen before plugging it in seems to help, but the success rate of this approach is not 100%.

I am wondering whether anyone else has been having the same issues (so that it will hopefully be fixed by a software update), or whether there is something uniquely wrong with my MacBook hardware-wise.
 
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Jonathan Field

macrumors newbie
Jan 2, 2020
1
0
London
Hello adding my experience here:

I was wondering if anyone could help me or if anyone has had a similar experience?

I have an LG 5K 27MD5KA Display that I've owned for around 1 year. It worked fantastically up until recently, I was on a video call using the built in web cam and heard a buzzing sound, the screen then went off and won't come back on. The monitor is continuing to deliver power over the Thunderbolt 3 connection just fine but under no circumstances will the monitor display any video output or show anything to suggest that it is connected. It is just black all the time (the backlight is not active).

My system is a 2018 MacBook Pro 13" I have tried Various versions of Mac OS

Resetting PRAM/NVRAM/SMC many many times
Different power cables 5 x different types of Thunderbolt 3 (Not USB-C) cables from multiple vendors including Apple, Belkin and Anker

Does anyone have any suggestions beyond sending in for repair? (my LG support experience in the past was not positive)
 

jimthing

macrumors 65816
Apr 6, 2011
1,455
690
London, UK (Europe, Earth, Space)
Hello adding my experience here:

I was wondering if anyone could help me or if anyone has had a similar experience?

I have an LG 5K 27MD5KA Display that I've owned for around 1 year. It worked fantastically up until recently, I was on a video call using the built in web cam and heard a buzzing sound, the screen then went off and won't come back on. The monitor is continuing to deliver power over the Thunderbolt 3 connection just fine but under no circumstances will the monitor display any video output or show anything to suggest that it is connected. It is just black all the time (the backlight is not active).

My system is a 2018 MacBook Pro 13" I have tried Various versions of Mac OS

Resetting PRAM/NVRAM/SMC many many times
Different power cables 5 x different types of Thunderbolt 3 (Not USB-C) cables from multiple vendors including Apple, Belkin and Anker

Does anyone have any suggestions beyond sending in for repair? (my LG support experience in the past was not positive)
Unlucky. Send in for repair, I'd suggest. Then come back and tell us all how well it went and how much it cost you.
 
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defn

macrumors regular
Apr 25, 2015
103
126
Never mind, the issue came back to me after several sleep/wakes too.

After a restart, sleep/wake works fine for a few cycles, then the external display gets woken up at max brightness, then it doesn't work at all.

Image retention *seems* to be getting worse, but I have no way of quantifying that.

LG Support in Hong Kong is pure rubbish, so I don't want to waste my time with them again either.

Just played around with a Pro Display XDR at the Apple Store yesterday and super tempted to order one now.
 

AppelGeenyus

macrumors member
Nov 3, 2019
36
31
Can anyone confirm if the uneven backlight issue is fixed yet? Specifically the big bright spot in the middle of the screen. I purchased and returned one of these about 3 or 4 times over ~1 year from 2017-2018, all went back mainly because of this issue. Even the ones I saw in stores had it. It just wasn't possible to do any real design work and totally unacceptable for the price tag, I could even notice it when scrolling down any white page with black text.

If you want to check, set your brightness to ~100 nits and display a totally white screen.
 

Johnny7790

macrumors newbie
Jan 18, 2020
1
0
I today purchased 2 of the new 24” 4K versions.

However, they both “tick” from the rear when turned off (connected to power but with the Mac in standby so the displays are off) and both sound exactly the same.

I believe this is due to an insulating material in the PSU vibrating against the PSU case.

No issues when powered on and in use by the Mac.

Can you all stick your head at the back of your UltraFines (when powered but turned off) and tell me what you hear? Does yours tick when turned off?

I love these displays, but if I exchange them will I get the same crap?

Does anyone know how to fix it? Maybe open up the back and tinker around.
 

oppastopa

macrumors member
May 25, 2019
33
17
I today purchased 2 of the new 24” 4K versions.

However, they both “tick” from the rear when turned off (connected to power but with the Mac in standby so the displays are off) and both sound exactly the same.

I believe this is due to an insulating material in the PSU vibrating against the PSU case.

No issues when powered on and in use by the Mac.

Can you all stick your head at the back of your UltraFines (when powered but turned off) and tell me what you hear? Does yours tick when turned off?

I love these displays, but if I exchange them will I get the same crap?

Does anyone know how to fix it? Maybe open up the back and tinker around.
On my 5K Refurb usually when I wake the display from sleep it makes these little 'click' noises. Sounds like the cheap plastic rattling around on the inside. Also usually occurs when I put the computer into sleep.
- - Post merged: - -

 

Spider2000

macrumors newbie
Jan 19, 2020
2
0
My 24” has constant tapping/rattling from back when computer in the standby. It ticks twice per second - V fast.

I can only heard it when there is of no ambient noise though (which is every of the time am actually in office). I never notice until the Johnny pointed this to me.

Does all of them do it.
 

marlowja

macrumors newbie
Jan 21, 2020
3
0
I just purchased the latest revision of the 27in 5K (the one that supports 4K over USB-C), which I'm using with my 12 inch MacBook until I upgrade to a MacBook Pro later this year.

I have had no video issues with the USB-C to USB-C connection (since the 12in MacBook does not support Thunderbolt), but I've had pervasive issues with audio, webcam, and USB-C peripherals cycling in and out of connection (e.g. the audio output will switch from my laptop to the monitor speakers every 5-10 seconds, since the computer cycles between recognizing the USB connection of the monitor and not.

I've done SMC reset, NVRAM, factory reset, updated to Catalina etc to no avail, I can't get the connection to stick, not even to conduct a firmware update with the LG Screen Utility app. Could it be a faulty USB-C cable, or a broader issue? I'd like to determine whether or not this is an issue with my laptop or with the monitor, before purchasing a laptop only to find that the monitor is faulty.

If anyone has experienced this issue, I'd appreciate it if you could share your experience or any other solutions. Thanks!
 

Successful Sorcerer

macrumors member
Nov 23, 2019
74
14
It sounds like a bandwidth issue but I'm not sure... I don't have one but if the 12" macbook only has usb-c connection it probably doesn't run in 5K, can you check? Thunderbolt 3 is 40GBps and usb-c 10 GBps which is four times slower. 5K resolution alone already needs 22 Gbps (4K 12GBps so 4K is even questionable). Knowing these facts my guess is that there isn't enough bandwidth for all functionalities.
 

marlowja

macrumors newbie
Jan 21, 2020
3
0
It sounds like a bandwidth issue but I'm not sure... I don't have one but if the 12" macbook only has usb-c connection it probably doesn't run in 5K, can you check? Thunderbolt 3 is 40GBps and usb-c 10 GBps which is four times slower. 5K resolution alone already needs 22 Gbps (4K 12GBps so 4K is even questionable). Knowing these facts my guess is that there isn't enough bandwidth for all functionalities.
It's running at 4K 48Hz over USB-C, which is expected behavior since that's the maximum the MacBook can support. When I force a lower, unscaled resolution like 1920 x 1080, the disconnection issue persists. Note that the MacBook at 4K via USB-C is officially supported by the latest revision of the 5K monitor (27MD5KL) alongside the iPad Pro, and it references USB-C mode audio output on the Apple Store page, so it should be supported.
 

Successful Sorcerer

macrumors member
Nov 23, 2019
74
14
It's running at 4K 48Hz over USB-C, which is expected behavior since that's the maximum the MacBook can support. When I force a lower, unscaled resolution like 1920 x 1080, the disconnection issue persists. Note that the MacBook at 4K via USB-C is officially supported by the latest revision of the 5K monitor (27MD5KL) alongside the iPad Pro, and it references USB-C mode audio output on the Apple Store page, so it should be supported.
Ok, if it's not scaled at 1080p then I don't know. It'd be interesting to know if all works fine on a newer mac with Thunderbolt 3 support. There seem to be more issues with 4K/5K screens (all screens not only LG) and older macs.
 

___joshuaturner

macrumors member
Dec 15, 2017
48
192
I know the majority in this thread are talking about the newest issue with this miserable display - but can anyone confirm that the newer models no longer have the image retention issue?

I got mine the first week they were released and the image retention is becoming a massive problem. I'm talking ~5 minute retention after only ~30 seconds on screen.

Is there something specific on the monitor I can look for that would indicate that it is newer and doesn't have the image retention issue? I've heard talk of squares/circles, etc.

Unfortunately there just isn't another 5k monitor out there with a similar ppi so I'm stuck here unless I want to drop way too much money on an XDR.
 
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darthaddie

macrumors member
Sep 20, 2018
50
37
Planet Earth
I bought an Ultra fine 5k last week. Been running great so far. No issues whatsoever except the dreaded Catalina brightness bug. No image retention as well. I left it on throughout the night by mistake and did not see any.

I am going to calibrate it this week along with my BENQ SW271. Compared to the LG, the BENQ looks...... well substandard. Lol

not going back from 5k...
 

___joshuaturner

macrumors member
Dec 15, 2017
48
192
Could you share the first 4 digits of your serial number? Apparently any starting with 90__ are better on image retention.
- - Post merged: - -

I bought an Ultra fine 5k last week. Been running great so far. No issues whatsoever except the dreaded Catalina brightness bug. No image retention as well. I left it on throughout the night by mistake and did not see any.

I am going to calibrate it this week along with my BENQ SW271. Compared to the LG, the BENQ looks...... well substandard. Lol

not going back from 5k...