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macrumors member
Original poster
Oct 4, 2018
Hello guay again

let me explain what o need:
I have a ElGato thunderbolt 3 pro Dock Word MacBook Pro. Now i want to connect this to my Mac Pro 5.1.

i bougth Sonnet Allegro USB-C PCIe to connect Theodore thunderbolt dock, but IT doesn’t Work.

the sonnet allegro card works, because if i connect Apple usb c adapter with a usb with mp3 for example, ir recognize the usb and i can listen music from the usb connected to sonnet allegro using Apple usb c adapter.

what i need to connect now elgato thunderbolt 3 pro to my Max pro 5.1?

when i connect my Max pro 5.1 doesn’t recognize, show an alert: “thunderbolt devices are not compatible...”

Si what i need?

i hope someone can help me thanks

Best regards

I attach the images for products
I attach the images for products


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Last edited:


macrumors member
Jan 23, 2017
From what I've read, some people have done this, but it's very, very unstable, and very difficult to do. I think you have to go through some configuration every time the Mac reboots, or maybe even goes to sleep. From what I recall, it was a lot of work, but not impossible.
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