MacPro 2015 to USB-C Monitor/dock through TB3 dock or Wacom Link Plus

[madmalkav]

So, I'm using a Wacom Link Plus I had lying around to test if I could use it to connect my MacBook Pro 2015 to a Lenovo P44W Monitor/Dock through USB-C.

If I use the HDMI connection from the computer to the Wacom device, everything works fine on the Lenovo: it uses the full native resolution 3840x1200 at 60hz fine.

If I try to do the same with a mDP to mDP cable, I get image for a second and then my monitor goes blank. It doesn't react to pushing any button (except power).

If I use mDP to mDP with a lower resolution i.e. activating the monitor 2 in 1 mode it will present itself to the Mac as a 1920x1200, it also works ok.

Being able to use mDP instead of HDMI would be great as the connector is placed on the MacBook in a much more convenient place for me, so I'm trying to figure out what can be causing this, but I have no clue. Any help appreciated.

 

[Bigwaff]

If I try to do the same with a mDP to mDP cable

The mDP cable that came with the Wacom?

What version of macOS installed?

 

[madmalkav]

No, a mDP cable I had lying around. Running Sonoma.

 

[Bigwaff]

No, a mDP cable I had lying around. Running Sonoma.

Possibly a low quality mDP cable... If running Sonoma then you must be using Open Core. Which version of OCLP?

In Somoma, have you tried --
Settings > Displays > Advanced button > Show resolutions as list (toggle on) .. then back in the main Settings > Display page, slide the Show all resolutions toggle to on. Do you see your desired resolution?

 

[madmalkav]

No, I don’t see the resolution if I do that, but I see it in BetterDisplay?

I have other cable on the way to discard that. It is probably that and I’m just overthinking this.

 

[madmalkav]

Same problem with a different cable 😭

 

[madmalkav]

I got a Startech Thunderbolt 3 dock and the problem is exactly the same. Seems like for some reason the Mac doesn't want to play nice with the USB-C connection to the monitor no matter what is in the middle. I was thinking about maybe an EDID issue, but not sure at all at this moment...

 

[madmalkav]

 

[madmalkav]

Oh #$^%@ I think I found it, the monitor have a button to change between video sources, and one button to change between USB data sources. But if you change the USB source in the menu, you can change the USB data speed, I change from 3.1 to 2.0 and now it works OK on both USB-C ports with Monterey.