I have some issue with my Macbook Pro 16 (BigSur).
Below 4 Macbook Pro thunderbolt ports, for clarity, I numbered the TB ports.
LID/LID/LID/LID/LID
1 ------------------- 2
3 ------------------- 4
I try to connect 4K LG monitor directly via thunderbolt->thunderbolt cable.
Now, mac gives me 720p max resolution with 30Hz on TB ports ( 2 and 4)
On ports ( 1 and 3) i have 4k resolution but only 30Hz and screen is little bit blurry :-/
Regardless of whether the GPU Switch is turned on (battery or power supply), the problem is the same.
That will be some TB issue, when I connect monitor through TB->HDMI adapter i have no problem with 4K 60Hz resolution.
Now same LG monitor and some other Macbook Pro 15 2017, same TB -> TB cable, 4k 60Hz no problem ...
How can I debug what happen with 16" mac ?
-
OK look's like Apple the big bug maker release something with latest update
https://piunikaweb.com/2021/01/08/external-4k-monitor-issues-after-macos-big-sur-11-1-update/
https://forums.macrumors.com/thread...s-no-longer-working-over-1080p.2275376/page-7
https://discussions.apple.com/thread/252174979?answerId=254318152022&page=19Last edited: Jan 26, 2021
Macbook Pro 16 Thunderbolt Low Resolution 30Hz Debug
Discussion in 'Apple and Mac OS X' started by syngress, Jan 26, 2021.