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LG UltraFine 5K - Owners Thread
- Thread starter iBrooker
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So what is it about Apple Silicon that the LG 5K doesnt like? I've got the LG, and an Apple Studio Display, typically I have my work M3 Max connected to the LG, and my personal M3 Max connected to the ASB (and on occasion, I connect both, depending on if I need an extra screen). The LG disconnects from the system, and I need to unplug/replug to get the screen to wake back up, and then the cycle repeats. Even went so far as to get a Belkin Pro Thunderbolt 4 dock from work, and same thing will happen, but all other items connected through the dock worked (Ethernet, USB smart card reader). I had the LG connected to a 2019 i9 previously, for near on 2 years and never had that problem. I've made sure firmware on the monitor is updated, checked the port on the monitor and it doesnt feel loose. Next thing I'd probably change would be the cable itself - any good recommendation for a replacement?
Any cable from a reputable brand rated as thunderbolt 3 or 4 will work, measure for the length you actually need and go with the shortest possible cable.
It would not hurt to try a new cable first but unfortunately, if i had to bet on it, your port is the culprit of your problem.
It doesn't necessarily need to feel loose in order for the port to fail. The symptoms you are describing is highly suggestive of solder cracks on the thunderbolt port which is a common reported defect of these monitors.
Charging your device via the monitor causes the port and solder to overheat over and over which ends up cracking the solder joint overtime. I assume you charged your 2019 i9 via the monitor for 2 years.
People suggest using a thunderbolt dock when you first get the monitor as a preventive measure to decrease wear and tear on the port and since we know the cause of why the port fails people also suggest charging the connected device with its own power supply rather than the monitor to avoid overheating the port.
If the port is already damaged obviously the thunderbolt dock would not provide any solution.
You can open it up fairly simple (search on youtube for tutorials) so that you can inspect the solder joints yourself, if you discover there is in fact cracks your options are: DIY replacing the entire board which you can probably find on ebay, create a paid repair directly with LG, or search for a computer repair shop that performs board repairs and is willing to attempt to re-solder the port which might or might not fix the issue.
Sorry
EDIT: here is a video of what you will be looking for when inspecting the port
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Thanks for that bit of info; and yes, I'd been using just the monitor to charge the 2019 when it was connected. Good thing is, I'm only $100 invested in this monitor (I bought it from work when they were selling 'old' monitors - they didnt know what they had). I'll look into doing some DIY repairs on it to see if I can fix it.
You got a heck of a deal, worse case scenario you could sell it for parts for more than what you paid, I just searched on ebay for a board replacement and they are quite expensive, i think the cheapest route would be getting it repaired by a computer repair shop, preferably one that has previously repaired this type of monitors. If they dont know what they are doing they can easily damage/tear the very small pins in the board, if that happens there is no fixing them because they are too small.
Good Luck
No shop can reliably repair these in my experience—it's a 50/50 chance, and you will still have to pay for the work. You also can't get the correct replacement board because LG doesn't actually sell them. Oh, they will sell you a replacement board, but the board they give is a RANDOM board from a RANDOM region. You'll probably get a V1, which had all sorts of shielding and EMI problems.
Your best best is finding a donor board from a SKU matching donor, but those are also very hard to find because the board is much more likely to fail than the panel or PSU.
Also this has just been my experience. If anyone ever finds a Authorized LG Service Partner who is somehow able to purchase the correct board, PLEASE update this thread.
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Soooo...I think there's something else at play here. I connected my test system that I have for work, which is a 2019 16-inch Intel, and the LG runs just fine on it. I've kept it up for hours, with no disconnects, and it waking properly after putting the machine to sleep. I connect to my M3, and within a few minutes it disconnects. I have power running to the Mac's from the power brick, just to take that out. When it disconnects from the M3, I switch plug to the Intel, and it turns on. Back to the M3, and I get nothing, OR it comes on and then will disconnect after. I also checked and made sure that the firmware on the monitor is updated, with the LG monitor app. I havent had time to take it apart yet to check the board, but hoping to do that this weekend.
This actually sounds very typical of the port failing, and is exactly what I have experienced. In a way it makes no sense, and I do not fully understand exactly why it fails with what appears to be "patterns", but I think it has something to do with the handshake required between the device and the display and specific pads/traces that have weakend to the corresponding pins. It almost seems like the display gets temporarily "locked" to a specific device, and fails the handshake when a new/different device is connected. I would always test between and Intel MBP and an iPad that supported DP over USB-C. When the port was failing on the LG the MBP seemed to either not connect at all or connect very intermittently, but the iPad seemed to connect 9/10 times. It drives you crazy because it doesn't seem to make any logical sense. It feels like a software bug of some kind. But the more research I did into the issue the more I realized that there is a LOT that happens when you plug in an USB-C cable. I have also experienced this weird intermitteness with a USB-C port on a MBP that intermittemently lost some of it's reverisbility… so it is also possible it's the USB-C port on the M3. Apple can diagnose this pretty easily. Very easy replacement on the old Intel MPB as the USB-C ports are on a daugher board. Not sure about the new Ms.
I have a few USB-C testers and USB-C cable testers to help try and diagnose USB-C issues, but even still it's very difficult. I have a C2C CaberQU which I use for testing USB-C cables now, and just by virtue of using it you can sort of see how certain pins can fail and cause intermittent issues. Hard to explain, but using this little board has given me a better understanding into just how delicate USB-C actually is. I actually can not remember if I ever had a full size USB-A port fail. Maybe once on a motheboard? And maybe I've seen a few USB Micro ports fail from physical wear and abuse, but USB-C… I've probably seen six or seven ports fail now, and at least as many cables.
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I have owned this product for almost 4 years now. Actually 2 of them. I only purchased it as it was the only monitor other than an HDMI connection that would work with my MacPro Desktop 7.1 2019 computer. The first one failed one month out of the one-year warranty with a failed screen with a repair costing more than a new one. LG refused to do anything about it other than to offer a negligible discount if I purchased a new one from them. So, I bought another one from Apple as it was still the only one available for my computer at the time with my 10% military discount that was much more than LG offered me, also thinking it would be covered by AppleCare, only to find out later that AppleCare only covers items made by Apple, even though the Apple Store sold it.
The App for it on the MacStore is useless other than for monitor upgrades which have not been issued for many years and a factory reset. Everything else is done by System Settings. It also has no contrast adjustment which creates issues for color calibration and makes using Apple's calibration tools next to useless. I have yet to be able to get a true color match between the monitor and my Kyocera P5026 color laser printer as it does not support ColorSync. Here are some things I have learned about this monitor:
- The output ports do not provide much power. They are easily overloaded and if so, will disable the monitor resulting in expensive repair.
- You can get additional settings for Apple Display Calibration by holding down the Option key when clicking on the Plus (+) sign when adding a custom display calibration. This provides some additional settings which offer minimal improvement but any improvement can be useful.
- No need to auto start LG screen manager as the monitor works 'fine' without it. I only launch it occasionally to check for updates.
- Amazon sells a Thunderbolt extension cable, USB4 Extension Cable 2.62Ft, Thunderbolt 3 & 4 Extension Cable, that works. I have my Mac on the floor on the side of my desk and the included was barely long enough to reach. Cables over 6' are very expensive. This extension is only $20.
Another thing I did was toss the included monitor stand and used the VESA mount plate to mount it to aStarTech.com Single Monitor Stand - Adjustable - Supports Monitors 12'' to 34'' from Amazon costing $95. This offers much more flexibility for the monitor position including rotation to portrait mode, abet not offering gas spring height adjustment, but only manual height adjustment that once properly sent rarely needs adjustment. This stand, while less user friendly, offers all the adjustments as Apple's $1000 stand for it premium $5000 monitor. Given I rarely adjust the monitor position, a little inconvenience is worth it to me for allowing me to save $49900.
Finally, if you want to avoid LG, Samsung also sells a 5K 27" monitor a few hundred dollars less than LG. However, I know nothing about it. There are also now a number of 4K 27" monitors available, some under $500. I suspect that unless you are into hires graphics as a profession or hobby, 4K is enough resolution for most.
The App for it on the MacStore is useless other than for monitor upgrades which have not been issued for many years and a factory reset. Everything else is done by System Settings. It also has no contrast adjustment which creates issues for color calibration and makes using Apple's calibration tools next to useless. I have yet to be able to get a true color match between the monitor and my Kyocera P5026 color laser printer as it does not support ColorSync. Here are some things I have learned about this monitor:
- The output ports do not provide much power. They are easily overloaded and if so, will disable the monitor resulting in expensive repair.
- You can get additional settings for Apple Display Calibration by holding down the Option key when clicking on the Plus (+) sign when adding a custom display calibration. This provides some additional settings which offer minimal improvement but any improvement can be useful.
- No need to auto start LG screen manager as the monitor works 'fine' without it. I only launch it occasionally to check for updates.
- Amazon sells a Thunderbolt extension cable, USB4 Extension Cable 2.62Ft, Thunderbolt 3 & 4 Extension Cable, that works. I have my Mac on the floor on the side of my desk and the included was barely long enough to reach. Cables over 6' are very expensive. This extension is only $20.
Another thing I did was toss the included monitor stand and used the VESA mount plate to mount it to aStarTech.com Single Monitor Stand - Adjustable - Supports Monitors 12'' to 34'' from Amazon costing $95. This offers much more flexibility for the monitor position including rotation to portrait mode, abet not offering gas spring height adjustment, but only manual height adjustment that once properly sent rarely needs adjustment. This stand, while less user friendly, offers all the adjustments as Apple's $1000 stand for it premium $5000 monitor. Given I rarely adjust the monitor position, a little inconvenience is worth it to me for allowing me to save $49900.
Finally, if you want to avoid LG, Samsung also sells a 5K 27" monitor a few hundred dollars less than LG. However, I know nothing about it. There are also now a number of 4K 27" monitors available, some under $500. I suspect that unless you are into hires graphics as a profession or hobby, 4K is enough resolution for most.