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I have 2 Apple monitors: An old LED Cinema Display that has a Mini DisplayPort and a slightly newer Thunderbolt Display with a Thunderbolt 2 connection.
I am currently using them both connected to my 2014 MBP with no issues.
I recently got a 2017 MBP and would like to see if there is ANY setup that will allow me to connect both monitors.
From what I've read, the TB3 to TB2 adapter will not work with the Mini DisplayPort.
Is there any other setup that people have used that has worked for them?
Thunderbolt is a multiplexing of several signals - PCIe bus, USB 3.1, power and DisplayPort. On the 2017 MBP you have at least 2 Thunderbolt 3 ports. This means you don't need to convert from TB to DP/mDP as the signal is already there.
The LED Cinema display uses an mDP interface and the Thunderbolt display requires a Thunderbolt connection.
So, all you need is a USB-C (Thunderbolt) to DisplayPort cable for the LED display, and a Thunderbolt 3 to 2 adapter you mentioned along with the Thunderbolt cable you already own (from the previous setup) for the Thunderbolt monitor.
So Apple's TB3 adapter is only for data... only real use I found is when using the old computer in Target Disk Mode to transfer all data to the new computer. (Time Machine is not very good at computer migration)
I have the exact same problem and after much search, came to this solution:
Keep in mind that the Cinema display also needs a USB-A connection (I'm guessing to provide power to some internal circuit for link negotiation?), so you'll need a separate adapter from USB-C to USB-A.
I'm also an amateur photographer and shoots with a Canon 5DsR, editing my photos using an AdobeRGB LG 4K display (10-bit color to support AdobeRGB). I've also tested the DisplayPort adapter on this display and it works flawlessly.
On a side note - reason why you'll need a separate adapter for USB-A instead of having the USB-A built-in to the DisplayPort adapter is that only way for USB-C to support DisplayPort data-rate is using Display Protocol, which turns a bi-directional USB connection (10Gbit/direction) to a uni-directional output port (20Gbit total). If you work out the math: 3840 * 2160 * 10-bit color per channel * 3 color channels (RGB) * 60 Hz = 15Gbit/s.
Simple answer: Yes. At my last position, I used a 2017 USB-C/Thunderbolt 3 only MacBook Pro with a Cinema Display (Thunderbolt 3 to miniDisplayPort adapter) and a Thunderbolt Display (Thunderbolt 3 to Thunderbolt 2 adapter).
It was neither ideal nor elegant, but it worked.
