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joevt

Contributor
Jun 21, 2012
6,689
4,086
Long time lurker (19 years or so) and first time poster.

Uh, so I think I read that the gofanco hdmi to displayport converter works for the 27MD5KA (OG non usb version)? I bought the converter, the mini displayport to lightning and the displayport to mini displayport. I wanted to hook it up to a PS4 and switch it out occasionally to my 2013 Mac Pro. It is not working.

Did I misread a post here or is my set-up wrong?
You misread that. Maybe it was referring to 22MD4KA, the original LG UltraFine 4K display?

27MD5KA requires Thunderbolt input. You would need to add a Thunderbolt add-in card to your HDMI to DisplayPort converter.

USB-C is not lightning.
Lightning is not Thunderbolt.
 
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thisisausername

macrumors newbie
Jul 5, 2023
1
0
Hello all!

Total newbie here. I've been going through posts for few days but i couldn't find a direct answer. Given specs of Asus's motherboards with built in TB4 controllers (with two DP ins) are a bit unclear. They are supposed to be equipped with Intel JHL8540s but their ability to multiplex two DP Ins to single TB4 is not given in specsheets.

Is anyone here uses a Proart Z790 motherboard or a similar motherboard with builtin TB4 controllers with two DP ins to run 27MD5KL at 5k60?

If yes, is it dual DP 1.2 ins or is a -single DP1.4 with DSC to TB4 to LG- for 5k at 60?
 

Daniel M8

macrumors newbie
Jul 6, 2023
5
0
Hello, I have LG Ultrafine 5K 27MD5KL and have connected it with the Belkin VR cable to RTX 3090 custom-built PC. I was wondering whether there is a chance of getting it to run 5k instead of the current 4k (no option to install TB PCIe card). I also experience the USB port on the monitor having a regular about 1-second disconnect. Does anyone have a similar setup?
 

etc

macrumors regular
Sep 27, 2008
198
36
Hello, I have LG Ultrafine 5K 27MD5KL and have connected it with the Belkin VR cable to RTX 3090 custom-built PC. I was wondering whether there is a chance of getting it to run 5k instead of the current 4k (no option to install TB PCIe card). I also experience the USB port on the monitor having a regular about 1-second disconnect. Does anyone have a similar setup?
You need TB PCIe card with two DisplayPort inputs to run UltraFine 5K at 5K.
 
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joevt

Contributor
Jun 21, 2012
6,689
4,086
Hello, I have LG Ultrafine 5K 27MD5KL and have connected it with the Belkin VR cable to RTX 3090 custom-built PC. I was wondering whether there is a chance of getting it to run 5k instead of the current 4k (no option to install TB PCIe card). I also experience the USB port on the monitor having a regular about 1-second disconnect. Does anyone have a similar setup?
You can try adding a custom timing for 5K 39Hz.
 
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joevt

Contributor
Jun 21, 2012
6,689
4,086
Total newbie here. I've been going through posts for few days but i couldn't find a direct answer. Given specs of Asus's motherboards with built in TB4 controllers (with two DP ins) are a bit unclear. They are supposed to be equipped with Intel JHL8540s but their ability to multiplex two DP Ins to single TB4 is not given in specsheets.

If yes, is it dual DP 1.2 ins or is a -single DP1.4 with DSC to TB4 to LG- for 5k at 60?
If it has two DP ins, then they can allow 5K60 for dual tile Thunderbolt displays like the LG UltraFine 5K (two DP 1.2 inputs from the same GPU).

There is currently no way to convert single tile HBR3 or DSC to dual tile 5K60. Maybe there's a super expensive video wall processor (that can do more than 4K) which can do the job. Or a super expensive FPGA that can take one HBR3 with DSC input and create two DisplayPort outputs.
 
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Daniel M8

macrumors newbie
Jul 6, 2023
5
0
Hello, thanks for the insight. One other creative way although not necessarily the cheapest way to connect to LG 5k display is through a motherboard, ASUS AM5 MBs with x670E chipset have dual usb4 ports that are able to power an external 5k display. It has been tested here:
https://www.reddit.com/r/ASUS/comments/123mgjx
 

omniatlas

macrumors member
Jul 31, 2004
82
0
Using the LG Ultrafine 24" 4K monitor.

Bidirectional Club3D cable didn't work for me; I would get into desktop but once the computer restarted it was black screen and I had to try different display ports before it would display again, so the connection wasn't reliable.

Bought the WACOM Link Plus as the OP mentioned, and it worked immediately!

Audio control by keyboard is linked up, and so is my mouse to the USB-C ports on the monitor. I can't get display to dim at this stage but will try the programs mentioned here.
 

Erpler

macrumors newbie
Jul 14, 2022
24
7
I'm still very curious if anyone with a new AMD Phoenix / 780M laptop or mini PC has tried directly connecting it to the USB4 port which should support TB3. Either that or other modern Intel systems with good TB support.
 

roger_doger719

macrumors newbie
Oct 31, 2023
4
0
Hello All!

Wonderful comments and suggestions. I could not decipher if having 2 x LG 5K (27MD5KL-B) monitors can run off my custom Windows 10 desktop? I'm running an ASUS ROG Strix B550-F Gaming WiFi II MOBO, AMD 5900x CPU (no gpu), Nvidia GeForce RTX 3060, and I have the ASUS Thunderbolt 4 add-on card. I can get 1 LG monitor to run fine... the other is detected through the Thunderbolt Control Panel... but the Nvidia 3060 says I need 2 Display Port cables? There's only 3 on the graphics card... what do I do to get the 2nd LG 5K monitor to work??? I'm sure some solution could work... I'm just running out of gas. Thanks for your help!!!

Best, Art
 

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joevt

Contributor
Jun 21, 2012
6,689
4,086
I could not decipher if having 2 x LG 5K (27MD5KL-B) monitors can run off my custom Windows 10 desktop? I'm running an ASUS ROG Strix B550-F Gaming WiFi II MOBO, AMD 5900x CPU (no gpu), Nvidia GeForce RTX 3060, and I have the ASUS Thunderbolt 4 add-on card. I can get 1 LG monitor to run fine... the other is detected through the Thunderbolt Control Panel... but the Nvidia 3060 says I need 2 Display Port cables? There's only 3 on the graphics card... what do I do to get the 2nd LG 5K monitor to work??? I'm sure some solution could work... I'm just running out of gas. Thanks for your help!!!
An LG UltraFine 5K display requires two DisplayPort 1.2 connections over Thunderbolt to achieve 5K60. Therefore you need two separate Thunderbolt controllers and 4 DisplayPort outputs to achieve 5K60 on two LG UltraFine 5K displays.

Your RTX 3060 only has three DisplayPort outputs and you only have one Thunderbolt add-in card.

Connect the 2nd LG UltraFine 5K display directly to the RTX 3060 using a DisplayPort + USB 2.0 to USB-C cable. Use CRU to create a custom timing of 5K39.

Maybe you can add a second Thunderbolt add-in card but it might not work without a Thunderbolt header to connect to. Maybe it's not a requirement for your add-on card. Some people get around this by flashing the Thunderbolt add-on card or by connecting 3.3V to the force power on pin of the Thunderbolt header cable.

Maybe you can connect a DisplayPort 1.4 MST Hub that supports DSC to the third DisplayPort output of the RTX 3060, then connect two DisplayPort outputs from the MST hub to the DisplayPort inputs of the 2nd Thunderbolt add-in card. If it works, the display would probably be limited to 8bpc since I haven't seen an MST hub that can decompress 10bpc.
 

roger_doger719

macrumors newbie
Oct 31, 2023
4
0
An LG UltraFine 5K display requires two DisplayPort 1.2 connections over Thunderbolt to achieve 5K60. Therefore you need two separate Thunderbolt controllers and 4 DisplayPort outputs to achieve 5K60 on two LG UltraFine 5K displays.

Your RTX 3060 only has three DisplayPort outputs and you only have one Thunderbolt add-in card.

Connect the 2nd LG UltraFine 5K display directly to the RTX 3060 using a DisplayPort + USB 2.0 to USB-C cable. Use CRU to create a custom timing of 5K39.

Maybe you can add a second Thunderbolt add-in card but it might not work without a Thunderbolt header to connect to. Maybe it's not a requirement for your add-on card. Some people get around this by flashing the Thunderbolt add-on card or by connecting 3.3V to the force power on pin of the Thunderbolt header cable.

Maybe you can connect a DisplayPort 1.4 MST Hub that supports DSC to the third DisplayPort output of the RTX 3060, then connect two DisplayPort outputs from the MST hub to the DisplayPort inputs of the 2nd Thunderbolt add-in card. If it works, the display would probably be limited to 8bpc since I haven't seen an MST hub that can decompress 10bpc.

Thanks Joevt!!! I've sadly learned about the 2 Display Port per 1 Thunderbolt requirement. Why didn't Nvidia design their cards to have even # of ports? Anywho, per the 2nd LG 5K monitor, I have tried several Display port to USB-C cables and no luck, also a Display port to mini display port cable, with an Apple mini display port (female) to Thunderbolt adapter (also no luck) as they aren't 2-way. I'm wondering if there are any other creative ways to get the 2nd LG 5K to work? It's ok if not 5K60. Is there a Plugable adapter, or other apparatus that's out there to get the last LG 5K to work? Anyone else know?
 

joevt

Contributor
Jun 21, 2012
6,689
4,086
Thanks Joevt!!! I've sadly learned about the 2 Display Port per 1 Thunderbolt requirement. Why didn't Nvidia design their cards to have even # of ports? Anywho, per the 2nd LG 5K monitor, I have tried several Display port to USB-C cables and no luck, also a Display port to mini display port cable, with an Apple mini display port (female) to Thunderbolt adapter (also no luck) as they aren't 2-way. I'm wondering if there are any other creative ways to get the 2nd LG 5K to work? It's ok if not 5K60. Is there a Plugable adapter, or other apparatus that's out there to get the last LG 5K to work? Anyone else know?
https://forums.macrumors.com/threads/alternative-to-the-belkin-vr-cable.2378619/
 
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joevt

Contributor
Jun 21, 2012
6,689
4,086
Wow, awesome! I had no idea this type of cable existed. Does it power the LG Thunderbolt display because of the powered USB adapter?
It is certainly not powering the LG Thunderbolt display. If it works, the USB connection will let you use the USB features of the display such as audio, camera, brightness control, USB ports... Maybe one of those USB features is the ability to make the display work since the darn thing has no buttons... Or maybe it won't work. Your mileage may vary.
 

roger_doger719

macrumors newbie
Oct 31, 2023
4
0
It is certainly not powering the LG Thunderbolt display. If it works, the USB connection will let you use the USB features of the display such as audio, camera, brightness control, USB ports... Maybe one of those USB features is the ability to make the display work since the darn thing has no buttons... Or maybe it won't work. Your mileage may vary.
I didn’t mean power the whole display, like its 12v AC to wall connection, but the signal. A powered thunderbolt connection.
 

etc

macrumors regular
Sep 27, 2008
198
36
Thanks Joevt!!! I've sadly learned about the 2 Display Port per 1 Thunderbolt requirement. Why didn't Nvidia design their cards to have even # of ports? Anywho, per the 2nd LG 5K monitor, I have tried several Display port to USB-C cables and no luck, also a Display port to mini display port cable, with an Apple mini display port (female) to Thunderbolt adapter (also no luck) as they aren't 2-way. I'm wondering if there are any other creative ways to get the 2nd LG 5K to work? It's ok if not 5K60. Is there a Plugable adapter, or other apparatus that's out there to get the last LG 5K to work? Anyone else know?
RTX 2xxx series and Quadro cards have 4 DP ports
 

artiqio

macrumors newbie
Dec 26, 2023
1
0
I've been trying to read this thread but it's been hard to follow. If I have the gen 1 5K Ultrafine, is there any way to connect my laptop with USBC (display port support) to my monitor? I don't need it to be 5k resolution. 4k@60fps is good enough
 

antibolo

macrumors 6502
Sep 27, 2017
269
441
I've been trying to read this thread but it's been hard to follow. If I have the gen 1 5K Ultrafine, is there any way to connect my laptop with USBC (display port support) to my monitor? I don't need it to be 5k resolution. 4k@60fps is good enough
First gen models absolutely require a Thunderbolt input, unfortunately.

Later models support plain USB-C input (which can be DisplayPort if you have a bidirectional DP to USB-C cable) though they are crippled to 4K (and you don’t get the USB hub, audio and camera).
 

etc

macrumors regular
Sep 27, 2008
198
36
First gen models absolutely require a Thunderbolt input, unfortunately.

Later models support plain USB-C input (which can be DisplayPort if you have a bidirectional DP to USB-C cable) though they are crippled to 4K (and you don’t get the USB hub, audio and camera).
Mine 2-gen works via USB-C including peripherals.
 

etc

macrumors regular
Sep 27, 2008
198
36
what cable do you use?
It's not just a cable, it's USB + DisplayPort to USB-C muxer - Wacom Link Plus (I have one and it works, but cable messy) for example.

Or PCI-e Sunix UPD2018 board.

Or if your GPU has onboard USB-C output, then you can use just a basic noname USB-C to USB-C cable (like the one shipped with the UltraFine 2-gen).

You can find more information about adding USB-C with DP Alt Mode to your device here:
 

aha081

macrumors newbie
Jan 24, 2024
3
2
Thanks for sharing!
I'm now successfully lighting up a 27md5kl via a Thunderbolt expansion card, but the system is unable to use the monitor's camera mic and speakers.
The hardware is:
ROG STRIX Z790-A GAMING WIFI
Asus thunderbolt 3-tr expansion card
rtx4090
Win11 latest version system
Cables used the thunderbolt cable that came with the monitor
Installed lg's osc, no other driver software installed.
(10bit settings need to go to nvidia control panel to set up.
Thanks~
 

oddbjornk

macrumors newbie
Jan 28, 2024
3
0
Hi! I just thought I'd report that I am using the LG Ultrafine 5k (27MD5KL-B) with Windows 11 in its full 5120x2880 glory with webcam, speakers and USB-hub all ok.

Hardware used:
Motherboard: ASUS ROG STRIX Z490-A GAMING
GPU: ASUS ROG Strix GeForce RTX 2060 OC
Thunderbolt expansion card: ASUS ThunderboltEX 3-TR
Display: LG 5K Ultrafine 27MD5KL-B

You need two Displayport-cables from the Nvidia card to the Thunderbolt card and the monitor works fine in any of the Thunderbolt sockets of the ThunderboltEX 3-TR. You need to enable a couple of settings in the motherboard BIOS to enable the Thunderbolt support. I will post screenshots of these settings.

The most annoying glitch with my configuration has been that after a soft reboot (because of e.g. a Windows Update reboot), the monitor shows the BIOS splash screen with the spinning Windows progress indicator and then goes blank with no way of turning in on. This happened about 50% of reboots. Cold boot always worked fine. I have tried every possible combination of disabling BIOS fast boot and Windows "fast startup", but to no avail. Trying to restart the Windows GPU driver using Ctrl+Shift+Win+B did not help either. BUT: today I discovered that if I have another monitor connected to the HDMI output of the Nvidia card everything works perfectly even after reboots! I hope this is helpful to someone struggling with the same problem.
 
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aha081

macrumors newbie
Jan 24, 2024
3
2
Hi! I just thought I'd report that I am using the LG Ultrafine 5k (27MD5KL-B) with Windows 11 in its full 5120x2880 glory with webcam, speakers and USB-hub all ok.

My hardware:
Motherboard: ASUS ROG STRIX Z490-A GAMING
GPU: ASUS ROG Strix GeForce RTX 2060 OC
Thunderbolt expansion card: ASUS ThunderboltEX 3-TR
Display: LG 5K Ultrafine 27MD5KL-B

You need two Displayport-cables from the Nvidia card to the Thunderbolt card and the monitor works fine in any of the Thunderbolt sockets of the ThunderboltEX 3-TR. You need to enable a couple of settings in the motherboard BIOS to enable the Thunderbolt support. I will post screenshots of these settings.

The most annoying glitch with my configuration has been that after a soft reboot (because of e.g. a Windows Update reboot), the monitor shows the BIOS splash screen with the spinning Windows progress indicator and then goes blank with no way of turning in on. This happened about 50% of reboots. Hard boot always worked fine. I have tried every possible combination of disabling BIOS fast boot and Windows "fast startup", but to avail. Trying to restart the Windows GPU driver using Ctrl+Shift+Win+B did not help either. BUT: today I discovered that if I have another monitor connected to the HDMI output of the Nvidia card everything works perfectly even after reboots! I hope this is helpful to someone struggling with the same problem.
After reading your reply, I checked the bios and realized that Thunderbolt Boot support: Enabled was not turned on, and when it was turned on, my microphone, etc. worked fine too~
 
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