?well, he has been with me for more than 3 years and there are no problems. although the series is unreliable. one of their firstNow you have jinxed it. I predict your display will fail by the end of the week!
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LG UltraFine 5K - Owners Thread
- Thread starter iBrooker
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Have you thought about Remote Desktop? Before my company locked it down, I would use Remote Desktop to access my work laptop (PC) and it would use all three screens at local resolutions. My Mac was connected to the screens and I'd RDP into my laptop. I'd then just use spaces where a swipe gesture on each screen would show me the other computer. I could even have one screen on my Mac and one on my PC. I could have all three monitors on the Mac, all three on the PC or any combination in between. Worked a charm until IT decided to kill that functionality after someone else was a victim of a ransomware attack.
Note: I was using Microsoft Remote Desktop for this functionality and am not sure what options exist to do this with 2 Macs--I don't think the Apple Remote Desktop functions as well, so maybe something else third party?
Same situation, except have not yet decided for the LG 5K. In case I will buy one I will run into same issue.
I searched for a KVM switch in advance. Could not find any thunderbolt KVM.
Have you tried to plug on Mac to the thunderbolt port and the other to one of the USB-c port simultaneously? Some USB ports emulate DP on other monitors.
But then, how can select which Mac is on screen??
I am thinking to give up on LG 5K because of this issue.
I searched for a KVM switch in advance. Could not find any thunderbolt KVM.
Have you tried to plug on Mac to the thunderbolt port and the other to one of the USB-c port simultaneously? Some USB ports emulate DP on other monitors.
But then, how can select which Mac is on screen??
I am thinking to give up on LG 5K because of this issue.
Most of the current MBP models don't have video ports connectors already. You need to put a Thunderbolt dock/hub in between your MacBook Pro and the KVM switch you pick.
Here is my setup for sharing two gaming monitors that are running 180hz and 144hz.
I found one listed under "LG Computer Screen" on my local craigslist for $100. Messaged just now. Pray for me peeps.
Hello fellow UltraFine owners!
My 5k started acting up yesterday (blurry screen and random black disconnects) til it finally died this morning. Been troubleshooting all afternoon. I'm using a higher end 15 inch MacBook Pro (2018). The UF charges the MacBook, but that's it.
What I've tried so far:
- Reset SMC and PRAM
- Tried 3 different TB cables (40gps, 100W). Yes, including the original one that came with the box
- Factory reset
- Tried different ports
- LG Screen Manager (this app does absolutely nothing for me). On Monterey it says "This monitor is not supported" and there's no firmware to download anywhere to update it manually.
- Rebooted with monitor plugged in / out
- Turned computer fully off with monitor plugged in / out
- Clamshell/closed laptop lid
Sometimes if I plug the TB in and out there's noticeable cursor lag on the MacBook for like a minute, but the UF remains black. It is connected via system report however, and it only shows 20gps.
Dear kind strangers - is there anything else I have left to try before I bid farewell to my monitor?
Thanks,
BSFE
My 5k started acting up yesterday (blurry screen and random black disconnects) til it finally died this morning. Been troubleshooting all afternoon. I'm using a higher end 15 inch MacBook Pro (2018). The UF charges the MacBook, but that's it.
What I've tried so far:
- Reset SMC and PRAM
- Tried 3 different TB cables (40gps, 100W). Yes, including the original one that came with the box
- Factory reset
- Tried different ports
- LG Screen Manager (this app does absolutely nothing for me). On Monterey it says "This monitor is not supported" and there's no firmware to download anywhere to update it manually.
- Rebooted with monitor plugged in / out
- Turned computer fully off with monitor plugged in / out
- Clamshell/closed laptop lid
Sometimes if I plug the TB in and out there's noticeable cursor lag on the MacBook for like a minute, but the UF remains black. It is connected via system report however, and it only shows 20gps.
Dear kind strangers - is there anything else I have left to try before I bid farewell to my monitor?
Thanks,
BSFE
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Completely disconnect both computer and LG from power source for a minute. Probably not going to work, though.
There is no difference: when connected using Thunderbolt then both displays can do 5 Gbps USB.
The newer model 27md5kl can be connected using USB-C DisplayPort Alt Mode which allows 4K60 (maybe 5K39 with custom timing) and USB 2.0. This mode allows compatibility with computers that don't have Thunderbolt.
Is anyone using a Thunderbolt 4 hub between the Mac and the LG to share the experience?
If the SSD is attached to the hub, it should allow getting full thunderbolt speeds, for instance around 2000 MB/s for Nvme SSD.
But is the LG still working correctly than, going to slip when the Mac goes to slip, dimming, wake up?
If the SSD is attached to the hub, it should allow getting full thunderbolt speeds, for instance around 2000 MB/s for Nvme SSD.
But is the LG still working correctly than, going to slip when the Mac goes to slip, dimming, wake up?
I am curious about hub performance as well as I'm updating my setup.
Currently I'm on an i9 16" with two 5K UltraFines where I have to plug a monitor on each side of the laptop. One monitor is attached to a CalDigit TB 4 Element Hub that also hosts an SSD drive. The other monitor is on a Dell TB dock.
I just ordered a 16" M1 Max to replace the i9 with goals of adding a 3rd LG. My hope is that I could use CalDigit's TS4 and have two of the monitors utilize one of the laptop's TB ports, but it sounds like I'm limited to one 5K monitor per port? Even if I'm limited to one monitor per port, what about the additional drives/accessories that would be attached to the dock? Would they have full performance?
LG UltraFine 5K uses about 29 Gbps so it will reduce write speed of a Thunderbolt NVMe to 11 Gbps (≈1300 MB/s). Those numbers are from calculation. Actual results may differ.
Actually, I have a Dell UP2715K which uses similar timing to the LG UltraFine 5K so I can test this. For these tests I'm using a Sabrent Rocket 4.0 2 TB NVMe in a Trebleet Thunderbolt enclosure, a CalDigit Element Hub, and a Mac mini 2018.
MB/s (read/write)
2727/2713 Direct connect to Mac mini 2018
2636/2337 Connect to Thunderbolt 4 hub (Goshen Ridge)
2703/2493 Connect to Thunderbolt 3 device (Alpine Ridge)
2658/838 Connect to Thunderbolt 4 hub with 5K display connected to same hub.
There appears to be a 400-500 MB/s penalty for the write speed when connected to the Thunderbolt 4 hub so my 1300 MB/s calculation translates to an actual result of 838 MB/s.
EDIT: added a Thunderbolt 3 device test to show it has similar drop in performance compared to Thunderbolt 4 device.
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One LG 5K per M1 Thunderbolt port (one such display for original M1 Macs, two for M1 Max, and three for M1 Pro). See my previous post regarding performance. Since you have 3 Thunderbolt ports, you should connect fast Thunderbolt devices to the 3rd Thunderbolt port.
Obviously, a 4K60 display uses less bandwidth (≈16 Gbps) than a 5K60 display. In that case, a Thunderbolt NVMe won't have a significant loss since 24 Gbps remains (Thunderbolt NVMe usually doesn't use more than 22 Gbps).
A 6K60 display actually uses less bandwidth (≈15.4 Gbps) than a 4K60 display because it uses DSC (for GPUs that support DSC).
Anyone use this with a Ultrafine 5K and two macs?
Seems to be the only exiting USB-c KVM switch, but the note for the Ultrafine 4K is confusing.
Seems to be the only exiting USB-c KVM switch, but the note for the Ultrafine 4K is confusing.
This thing won't handle dual-link-SST-via-Thunderbolt displays like the LG UltraFine 5K at full resolution. The best you'll be able to get via single-link DisplayPort 1.2 SST (USB-C!) is "4K" at 60 Hz (or 5K at 39 Hz using custom timings)... if you have the newer model (27MD5KL).
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https://www.amazon.com/ConnBull-Splitter-Bi-Direction-Supports-Compatible/dp/B09MQ4N8KM - Reviewer says does not support TB.
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As if that is a surprise
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
No, but like a lot of folks the reviewer got one to try anyway.As if that is a surprise
Well, it could work if it could handle 20Gbps data. Some simple Thunderbolt extensions work https://egpu.io/forums/psu-cables/90-degree-angle-usb-c-adapter/paged/2/#post-66724
but a switch is more complicated.
Switching Thunderbolt isn't something I would want to do often - Thunderbolt includes PCIe tunnelling and PCIe hot plug might not be as reliable as USB hot plug.
At least it would reduce wear on the Thunderbolt cable/port.
but a switch is more complicated.
Switching Thunderbolt isn't something I would want to do often - Thunderbolt includes PCIe tunnelling and PCIe hot plug might not be as reliable as USB hot plug.
At least it would reduce wear on the Thunderbolt cable/port.
The switch still couldn't handle a dual-link SST over Thunderbolt 3 setup then though.
Just got my Ultrafine 5K and noticed that the display is not straight. If I put the base parallel to the edge of the desk, the screen turns very slightly to the right (There is a little bit of a play in the height adjustment mechanism, I can wiggle the screen to the left or right a little bit). Plus, the left can be rotate up a lot more than the right, but within the range of rotation, the screen can be adjusted to be level.
It seems the display is not super precisely built, especially comparing to the Thunderbolt Display I used before this. Is this normal? If this is indeed the normal built quality, I would not bother exchanging one since the screen itself has no issues.
It seems the display is not super precisely built, especially comparing to the Thunderbolt Display I used before this. Is this normal? If this is indeed the normal built quality, I would not bother exchanging one since the screen itself has no issues.
I mean 4 lines of 20 Gbps signals. Thunderbolt has two bi-directional (full duplex) lanes of 20 Gbps = 40 Gbps each direction = 80 Gbps total.
The switch is meant for 10 Gbps signals, 4 lines = 40 Gbps total.
