I have a 2017 15" MBP along with 2x 1080p displays and 1x 4k display. The spec sheet for the MBP states that it supports 4x 4k 60Hz connections alongside the built in display.
I purchased a Cable Matters Thunderbolt Dock: https://www.amazon.com/dp/B06ZZPZL5N/ref=emc_b_5_t
This dock supports video output via Thunderbolt and Displayport. I attached one of my 1080p displays along with the 4k display directly to the dock. With only these two attached everything works as expected. If I then attach the 2nd 1080p display (3rd display total) directly to the MBP one of two things will happen. Either the 1080p display attached direct to the MBP will stop working and no longer be detected by MacOS, or the 1080p display attached to the TB dock will stop working and no longer be detected by MacOS.
I tried swapping things around so the 4k attached direct to the MBP and the 2x 1080p displays were attached to the dock and I witnessed the same behavior. Without the 4k attached both 1080p displays would work via the dock, but the moment I plugged in the 4k display one of them would cut out.
Finally I attached one 1080p display and the 4k display direct to the MBP and just one of the 1080p displays to the dock and finally all 3 displays work!
So my question is, has anyone else encountered similar behavior before and have any solutions on how to get 2x displays working via the dock with a third display attached direct to the MBP? I already checked and there are no MacOS drivers to download for this dock. Obviously I could go on with driving only one display via the dock, but that somewhat defeats the point of why I purchased the dock in the first place.
Thank you in advance!
I purchased a Cable Matters Thunderbolt Dock: https://www.amazon.com/dp/B06ZZPZL5N/ref=emc_b_5_t
This dock supports video output via Thunderbolt and Displayport. I attached one of my 1080p displays along with the 4k display directly to the dock. With only these two attached everything works as expected. If I then attach the 2nd 1080p display (3rd display total) directly to the MBP one of two things will happen. Either the 1080p display attached direct to the MBP will stop working and no longer be detected by MacOS, or the 1080p display attached to the TB dock will stop working and no longer be detected by MacOS.
I tried swapping things around so the 4k attached direct to the MBP and the 2x 1080p displays were attached to the dock and I witnessed the same behavior. Without the 4k attached both 1080p displays would work via the dock, but the moment I plugged in the 4k display one of them would cut out.
Finally I attached one 1080p display and the 4k display direct to the MBP and just one of the 1080p displays to the dock and finally all 3 displays work!
So my question is, has anyone else encountered similar behavior before and have any solutions on how to get 2x displays working via the dock with a third display attached direct to the MBP? I already checked and there are no MacOS drivers to download for this dock. Obviously I could go on with driving only one display via the dock, but that somewhat defeats the point of why I purchased the dock in the first place.
Thank you in advance!
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