LG UltraFine 5K and 2013 Mac Pro: does the webcam etc. work over TB2?

[valdikor]

I plan to get an LG UltraFine 5K Display for my trusty old 2013 trash can Mac Pro (later on, I will replace it with a future Apple Silicon Mac mini or something like that).

I realize and I’m fine that it will only run in 4K through the Thunderbolt 3 to 2 adapter, but one thing it could not find an answer to is whether the webcam, speakers, microphone, and USB-C ports will work over the legacy Thunderbolt 2 connection.

I’d be fine if the USB-C ports don’t work (or only work with USB 2.0 speeds), but the webcam, mic and speakers not working would be a deal-braker.

 

[joevt]

I think they should work.

Thunderbolt 2 is 20 Gbps.
DisplayPort 1.2 HBR2 is up to 17.28 Gbps.
USB 3.0 is 4 Gbps.

4K60 is 16 Gbps (10 bpc) or 12.8 Gbps (8 bpc). You might be able to get 5K39 8bpc (14.5 Gbps) using a custom timing (created with SwitchResX). Actually, the GPUs (or the Apple drivers) of the MacPro6,1 have a bug with 5K width (I haven't tested it recently).
https://forums.macrumors.com/threads/lg-49wl95c-mojave-5120-x-1440-support.2239781/post-28532915
https://forums.macrumors.com/threads/intel-graphics-and-5120x1440-testing-in-big-sur.2244174/

If a Thunderbolt 2 connection doesn't work, and you're getting the latest LG UltraFine 5K that supports either Thunderbolt 3 and USB-C connections, then you can connect a bidirectional USB-C to DisplayPort cable or a cable/adapter that combines DisplayPort and USB 2.0 to USB-C.
https://egpu.io/forums/gpu-monitor-...sb-c-to-displayport-cable/paged/4/#post-79127

 

[valdikor]

I think they should work.

Thanks a lot for your in-depth reply, I really appreciate it.

I have now ordered the display, but it seems the supply is pretty thin, so it might a week or two before I get it.

I’ll be hooking it up using the Thunderbolt 2 adapter, hope it works.

I’d like to run it at 60Hz, so I think I’ll just go 4K but I might experiment with SwitchResX too, it’s worth at least a shot.

I’ll post here again when I have received and tested the display.

 

[Amethyst1]

I’ll be hooking it up using the Thunderbolt 2 adapter, hope it works.

A couple of years ago they had the original UF 5K hooked up to a 2013 Mac Pro using that adapter in my local Apple Store and it definitely worked. I didn't dare install SwitchResX to check the actual resolution/timing though.

 

[Amethyst1]

@joevt - out of curiosity... Assume one were to put a GC-Alpine/Titan Ridge card in a Thunderbolt enclosure, connect a Thunderbolt cable from the Mac Pro to the enclosure and two DisplayPort cables from the Mac Pro to the card. Would this (theoretically) allow the UF to work at 5K 60 Hz and with all features from a 2013 Mac Pro (and e.g. the 2015 15" MBP)?

 

[rawweb]

I plan to get an LG UltraFine 5K Display for my trusty old 2013 trash can Mac Pro (later on, I will replace it with a future Apple Silicon Mac mini or something like that).

I realize and I’m fine that it will only run in 4K through the Thunderbolt 3 to 2 adapter, but one thing it could not find an answer to is whether the webcam, speakers, microphone, and USB-C ports will work over the legacy Thunderbolt 2 connection.

I’d be fine if the USB-C ports don’t work (or only work with USB 2.0 speeds), but the webcam, mic and speakers not working would be a deal-braker.

As a previous Ultrafine 5k and 2013 6,1 owner, yes, I can confirm all features (camera, sound, USB) of the Ultrafine work minus full 5k resolution. It will upscale 4k to 2560x1440.

I used a Blackmagic eGPU to drive it full 5k with the old Mac Pro.

@joevt - out of curiosity... Assume one were to put a GC-Alpine/Titan Ridge card in a Thunderbolt enclosure, connect a Thunderbolt cable from the Mac Pro to the enclosure and two DisplayPort cables from the Mac Pro to the card. Would this (theoretically) allow the UF to work at 5K 60 Hz and with all features from a 2013 Mac Pro (and e.g. the 2015 15" MBP)?

I once tried a titan ridge card inside a tb3 enclosure with the DP cables connected to an eGPU and was able to achieve a 5k image, however, the camera, USB, and sound features did not function (I knew they wouldn't). It was also very tricky to get the image to display, a lot of on/off tinkering with the titan enclosure and ultrafine if memory serves. Basically it was working only in DisplayPort passthrough mode as the titan ridge card was not enumerated in MacOS unless booting first to windows then warm over to MacOS. Maybe these days someone has found a work around to that problem. The gist is, unless the card is enumerated, it's thunderbolt features won't work. I suspect the same problem would occur if connected directly to the 6,1, however, I never thought to try that combo before I returned the trial enclosure as the setup was too messy.

 

[joevt]

@joevt - out of curiosity... Assume one were to put a GC-Alpine/Titan Ridge card in a Thunderbolt enclosure, connect a Thunderbolt cable from the Mac Pro to the enclosure and two DisplayPort cables from the Mac Pro to the card. Would this (theoretically) allow the UF to work at 5K 60 Hz and with all features from a 2013 Mac Pro (and e.g. the 2015 15" MBP)?

You should be able to get 5K60 (if you can get it to turn on) but the USB features (brightness control, audio, etc.) would require additional software (that doesn't exist yet) to enable. I don't think the software would be impossible, since warm booting from Windows is sufficient for the GC-TITAN RIDGE.

I have a GC-ALPINE RIDGE and a GC-TITAN RIDGE but haven't done much with them in my MacPro3,1 except:
1) enable USB for the GC-ALPINE RIDGE (but not Thunderbolt)
2) use Thunderbolt on the GC-TITAN RIDGE by warm booting from Windows first (USB works without modification or tricks)
3) use USB on a ASUS ThunderboltEx 4 (no modifications, jumpers, or tricks required)

#3 is interesting because it's USB4 and the USB4 spec is freely available so someone could make a driver for that regardless of macOS version (but I haven't verified that Thunderbolt can work without the header connection).

Other people have done stuff like flash the cards with Mac Thunderbolt firmware, or add SSDT to ACPI for hot plug, etc but there's issues with some of that.

 

[vanzeclipse]

I'm in the same boat and will be running dual UF 5Ks from a 2013 mac pro. My question is about adapters. Do I have to go with the apple tb3 to tb2 adapter or can I purchase these? https://www.amazon.com/USB-Mini-Dis...077G5W12W/ref=cm_cr_arp_d_product_top?ie=UTF8

There's no mention of thunderbolt 2, just display port, so I'm worried the sound and camera from the monitors may not work. Am I just overthinking this?

Thanks in advance.

 

[Amethyst1]

can I purchase these?

Absolutely not. You do need the Thunderbolt 3 to Thunderbolt 2 adapter and a Thunderbolt 2 cable for each monitor.

Reasons:

1. These USB-C adapters go from USB-C to DisplayPort. You'd need the other way round. But...
2. Even if they went from DisplayPort to USB-C, they would only work with the newer UltraFine 5K model. The older model will only accept video via Thunderbolt.

You do know the monitors will only run at 4K from the 2013 Mac Pro, right? You'll still be getting all the scaled options though. It just won't look as good as native 5K.

 

[joevt]

I'm in the same boat and will be running dual UF 5Ks from a 2013 mac pro. My question is about adapters. Do I have to go with the apple tb3 to tb2 adapter or can I purchase these? https://www.amazon.com/USB-Mini-Dis...077G5W12W/ref=cm_cr_arp_d_product_top?ie=UTF8

Unless a USB-C to DisplayPort adapter or cable says it is bi-directional, it is probably not bi-directional.

There's no mention of thunderbolt 2, just display port, so I'm worried the sound and camera from the monitors may not work. Am I just overthinking this?

Right. USB-C to DisplayPort adapters or cables do not do Thunderbolt. If you have the new model LG UltraFine 5K (27MD5KL) instead of the old Thunderbolt only (27MD5KA) version, and you want to connect via USB-C instead of Thunderbolt, and you want to use the USB features of the display, then you can use an adapter or cable that combines USB 2.0 and DisplayPort 1.2 to USB-C, such as the Wacom Link Plus or the Belkin Charge and Sync cable. https://egpu.io/forums/gpu-monitor-...sb-c-to-displayport-cable/paged/4/#post-79127
But that would limit you to USB 2.0. Since you have a Thunderbolt 2 port, you should get an Apple Thunderbolt 3 to Thunderbolt 2 Adapter to connect the Thunderbolt 3 displays.

Maybe the simplest way to get 5K on the displays is to connect them to a Blackmagic or Sonnet 5500 XT or 5700 eGPU (one eGPU per display). You'll need software to enable eGPUs for the Thunderbolt 2 Mac.
https://egpu.io/forums/mac-setup/kr...u-support-with-filevault-sip-and-art-enabled/

 

[vanzeclipse]

Absolutely not. You do need the Thunderbolt 3 to Thunderbolt 2 adapter and a Thunderbolt 2 cable for each monitor.

Reasons:

1. These USB-C adapters go from USB-C to DisplayPort. You'd need the other way round. But...
2. Even if they went from DisplayPort to USB-C, they would only work with the newer UltraFine 5K model. The older model will only accept video via Thunderbolt.

You do know the monitors will only run at 4K from the 2013 Mac Pro, right? You'll still be getting all the scaled options though. It just won't look as good as native 5K.

Yes, I am aware I would also need a TB2 cable as well as the adapter. Sorry, I may not have been clear on my question. I was asking if I have to use authentic apple tb3 to tb 2 adapter or would the posted generic one work the same? And the models of the LG 5Ks are 27MD5KLB-B, which I think are the newest ones?

Also, yes, I am okay with getting 4K for now until I upgrade the 2013 mac pro a little down the road.

 

[vanzeclipse]

Unless a USB-C to DisplayPort adapter or cable says it is bi-directional, it is probably not bi-directional.


Right. USB-C to DisplayPort adapters or cables do not do Thunderbolt. If you have the new model LG UltraFine 5K (27MD5KL) instead of the old Thunderbolt only (27MD5KA) version, and you want to connect via USB-C instead of Thunderbolt, and you want to use the USB features of the display, then you can use an adapter or cable that combines USB 2.0 and DisplayPort 1.2 to USB-C, such as the Wacom Link Plus or the Belkin Charge and Sync cable. https://egpu.io/forums/gpu-monitor-...sb-c-to-displayport-cable/paged/4/#post-79127
But that would limit you to USB 2.0. Since you have a Thunderbolt 2 port, you should get an Apple Thunderbolt 3 to Thunderbolt 2 Adapter to connect the Thunderbolt 3 displays.

Maybe the simplest way to get 5K on the displays is to connect them to a Blackmagic or Sonnet 5500 XT or 5700 eGPU (one eGPU per display). You'll need software to enable eGPUs for the Thunderbolt 2 Mac.
https://egpu.io/forums/mac-setup/kr...u-support-with-filevault-sip-and-art-enabled/

That was my concern. My IT person said it was the same as the genuine apple adapters. They have already placed the orders for the startech.com branded adapters and tb2 cables....I guess I'll see if they work or not, but if they only show video, then I'm okay with that until I upgrade the mac pro or another that has tb3.

I have the 27MD5KLB-B models, btw. Excited to see what these bad boys look like even at 4k. I'm coming from dual 27" thunderbolt displays.

 

[joevt]

Yes, I am aware I would also need a TB2 cable as well as the adapter. Sorry, I may not have been clear on my question. I was asking if I have to use authentic apple tb3 to tb 2 adapter or would the posted generic one work the same? And the models of the LG 5Ks are 27MD5KLB-B, which I think are the newest ones?

The adapter you posted is not for Thunderbolt 2 signals (10 Gbps per lane, two lines for transmit and two lines for receive). It is for DisplayPort signals only (5.4 Gbps per lane, four lanes, transmit only).

There are non-Apple Thunderbolt 3 to Thunderbolt 2 adapters (e.g. https://www.startech.com/en-us/cables/tbt3tbtadap ) but they are usually more expensive, and they only allow connecting Thunderbolt 2 devices to Thunderbolt 3 hosts. The Apple adapter is usually the least expensive, and it is bidirectional so that it can also be used to connect Thunderbolt 3 devices to Thunderbolt 2 hosts - which is what you need in your case.

That was my concern. My IT person said it was the same as the genuine apple adapters. They have already placed the orders for the startech.com branded adapters and tb2 cables....I guess I'll see if they work or not, but if they only show video, then I'm okay with that until I upgrade the mac pro or another that has tb3.

I don't think you can use Thunderbolt 2 cables for DisplayPort so even if that StarTech.com adapter was bi-directional (probably isn't), it still wouldn't work. That adapter requires a Mini DisplayPort cable and is probably only for connecting a USB-C host to a Mini DisplayPort display.
https://support.apple.com/en-ca/guide/mac-help/mh35952/mac

If you want to be cheap and not do Thunderbolt or USB to your displays, then you need a Mini DisplayPort to DisplayPort adapter and a bidirectional USB-C to DisplayPort cable.

 

[vanzeclipse]

The adapter you posted is not for Thunderbolt 2 signals (10 Gbps per lane, two lines for transmit and two lines for receive). It is for DisplayPort signals only (5.4 Gbps per lane, four lanes, transmit only).

There are non-Apple Thunderbolt 3 to Thunderbolt 2 adapters (e.g. https://www.startech.com/en-us/cables/tbt3tbtadap ) but they are usually more expensive, and they only allow connecting Thunderbolt 2 devices to Thunderbolt 3 hosts. The Apple adapter is usually the least expensive, and it is bidirectional so that it can also be used to connect Thunderbolt 3 devices to Thunderbolt 2 hosts - which is what you need in your case.


I don't think you can use Thunderbolt 2 cables for DisplayPort so even if that StarTech.com adapter was bi-directional (probably isn't), it still wouldn't work. That adapter requires a Mini DisplayPort cable and is probably only for connecting a USB-C host to a Mini DisplayPort display.
https://support.apple.com/en-ca/guide/mac-help/mh35952/mac

If you want to be cheap and not do Thunderbolt or USB to your displays, then you need a Mini DisplayPort to DisplayPort adapter and a bidirectional USB-C to DisplayPort cable.

So just as expected....the startech cords that were ordered did not work.

I just went out and picked up authentic apple cables and adapters....and it still doesn't work.

 

[Amethyst1]

just went out and picked up authentic apple cables and adapters....and it still doesn't work.

Which ones did you buy specifically?

 

[vanzeclipse]

Which ones did you buy specifically?

The ones listed here - https://www.slashgear.com/lg-ultrafine-5k-works-with-older-macs-needs-an-adapter-20468250/

Apple Thunderbolt Cable (2.0 m) - White

Apple Thunderbolt Cable lets you conduct fast data transfers by connecting Thunderbolt-enabled devices to your Mac. Get fast, free shipping.

www.apple.com

Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter

Effortlessly connect your Mac to a Thunderbolt 2 device with the Apple Thunderbolt 3 Adapter. Buy now at apple.com

www.apple.com

 

[vanzeclipse]

Got it to work with the apple cables. Just had to yank out everything, restarted as the only monitor and it turned on.

Now...the thing is only displaying max resolution at 3360 x 1890. Would there be another way to find out what the screen resolution is? This is from https://bestfirms.com/what-is-my-screen-resolution/

 

[Amethyst1]

Now...the thing is only displaying max resolution at 3360 x 1890. Would there be another way to find out what the screen resolution is?

Install SwitchResX and double-click the active resolution in the "available resolutions" tab. Look what it says for "active" (horizontal and vertical).

Forget this "stupid" website, as it only displays the scaled ("looks like") HiDPI resolution which doesn't match the monitor's actual resolution.

 

[vanzeclipse]

Install SwitchResX and double-click the active resolution in the "available resolutions" tab. Look what it says for "active" (horizontal and vertical).

Forget this "stupid" website, as it only displays the scaled ("looks like") HiDPI resolution which doesn't match the monitor's actual resolution.

Awesome, thanks! There's a current resolution tab with a check box for "show best resolutions for display in bold" it does indeed show 3840x2160 without being scaled.

It's a great program, but I just accidental selected two options and now my screen turned black. Going to restart and see if that helps.

 

[joevt]

Awesome, thanks! There's a current resolution tab with a check box for "show best resolutions for display in bold" it does indeed show 3840x2160 without being scaled.

A current resolution option that is Bold or not scaled just means the resolution and refresh rate is an actual timing. None of the numbers tell you what the actual resolution of the display is. Usually the timing with the maximum width and height is the resolution of the display except in your case you saw 4K instead of 5K. In my case, my 4K display can accept a 6K or 8K timing. I suppose you have to look at the unmodified EDID to know the actual resolution of a display (if you don't want to look up the specs at the manufacturer's product page).

If you see a 4K 60Hz timing, you can double click it to examine the timing info. 594MHz is for HDMI 2.0 timing and 533MHz is for CVT-RB timing.

Look for the currently selected resolution in SwitchResX. In the example you gave previously, it should be 3360 x 1890 HiDPI Scaled. If you double click it, you should see Active 3840 x 2160 and Scaled 6720 x 3780.

Since you have a Mac Pro 2013 and are not using an eGPU, then 3840 x 2160 is about as good as your going to get.
But you could try some custom resolutions to see how they look:
4096x2304 59Hz
5120x2880 39Hz

I am guessing at the refresh rates. You may need to try lower. You can also try higher. Just create all the custom timings at once in SwitchResX (use the Duplicate button after creating the first one), type Command-S to save, then click the Activate Now button, or unplug and connect the display.

It's a great program, but I just accidental selected two options and now my screen turned black. Going to restart and see if that helps.

While testing custom timings, it's useful to have a second display connected, or another Mac and use screen sharing.

 

[Amethyst1]

5120x2880 39Hz

Wouldn't this cause corruption due to the GPU(s) not being capable of handling timings wider than 4096?

 

[joevt]

Wouldn't this cause corruption due to the GPU(s) not being capable of handling timings wider than 4096?

Probably. But it would be interesting for the user to know what that looks like, and for us to know that it is still a problem and also that the display can accept the timing even though the GPU doesn't do it properly. The GPU can output the timing (it's stable and the display can accept it) but it's not doing the pixels correctly (they are out of order or something). Also, I'm not 100% sure it's a problem at all refresh rates (I no longer have a MacBook Pro 15 inch 2015 to test this).

 

[Amethyst1]

Also, I'm not 100% sure it's a problem at all refresh rates (I no longer have a MacBook Pro 15 inch 2015 to test this).

A Radeon HD 7770 on 10.9.5 showed the problem at 4098×2304 30Hz FWIW.

 

[joevt]

A Radeon HD 7770 on 10.9.5 showed the problem at 4098×2304 30Hz FWIW.

Right. It probably affects all refresh rates. I wonder if Boot Camp or Linux can do it correctly.