MP 7,1 6950 XT with working Studio Display?

[realLucaR]

Hello everyone,

I have a 2019 Mac Pro and I am trying to figure out how I can get my Studio Displays to work with a 6950 XT.

I have a W6800X Duo, but someone just offered me 3000 Euros for it, which I really just cannot refuse, I would be perfectly fine with one or two 6950 XTs (flashed of course)

But how can I get my Studio Displays (2x) to work with it? The Studio Display gives me 5k output over the USB-C port on the 6950 XT (reference), but brightness control, audio, microphone, webcam etc do not work. What can I do?

 

[joevt]

You need a cable or adapter that converts USB 2.0 + DisplayPort 1.4 HBR3 x4 to USB-C.
https://dancharblog.wordpress.com/2020/07/20/add-usb-c-with-dp-alt-mode-to-your-desktop-pc/

The Sunix UPA2015 looks interesting to me. It can support both USB 3.x + HBR3 x2 and USB 2.0 + HBR3 x4 devices.

It might be interesting if you could get a USB4 or Thunderbolt3/4/5 add-in card working in the Mac Pro. It could allow the same connections as the Sunix UPA2015. A Thunderbolt connection may also be possible but is much less likely.

The Level 1 Techs USB-C Combiner is nice because it has a switch that allows switching between USB 3.x + HBR3 x2 and USB 2.0 + HBR3 x4 modes.

If you don't have a Thunderbolt connection, then you need HBR3 x4 to have enough bandwidth for 5K120 and you'll be limited to USB 2.0 for the USB features of the display.

You shouldn't need any of the above because your 6950 XT has a USB-C port but you said the USB-C port of the 6950 XT doesn't allow you to use the USB features of the Studio Display. I guess first we need to confirm that the features are USB related and that the USB controller of the 6950 XT is working. What does the Studio Display look like in the ioreg output from Terminal.app when connected to the W6800X Duo vs when it is connected to the 6950 XT? Use the ioreg command in each case. zip the results and post here.

ioreg -fliw0 > ioreg_StudioDisplay_W6800XDuo.txt
ioreg -fliw0 > ioreg_StudioDisplay_6950XT.txt

Can you connect any other USB device to the USB port of the 6950 XT, such as a keyboard or storage device?