Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

iMac Pro 4k 60Hz External Monitor

Hello,


I have an entry level 2017 iMac Pro running Mojave 10.14.6 which is connected to

an Apple USB-C to HDMI adapter, which is connected to

an AmazonBasics 15ft Premium HDMI cable (18Gbps) which is connected to

a 2018 Vizio P-Series 55" screen


Despite the fact that each link in that chain supports 4k at 60Hz, when I check the system information on the iMac Pro, it shows that I'm only displaying at 30Hz:



What's going on here? What am I missing?



iMac Pro, macOS 10.14

Posted on Jul 12, 2021 2:18 PM

Reply
Question marked as Best reply

Posted on Jul 14, 2021 4:06 PM

Unsurprisingly, Apple tech support was in no way helpful.


I did find this thread which was helpful. I downloaded EasyRes, which allows you to chose between ALL of the display options/refresh options for a given display. Now my display is running 3840x2160 at a 60Hz refresh rate. Solved.

Similar questions

4 replies

Jul 13, 2021 3:46 PM in response to JCorHelps

Display preferences aren't any help. There's no option in display preferences to change the display's refresh rate (even when I option-click "scaled" on the second monitor's settings box).


Unfortunately I do not have another 55" 4k monitor handy. I have tested with other cables, as well as other adapters, all rated for 4k 60Hz. No luck with any of them.

iMac Pro 4k 60Hz External Monitor

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.