External display works on 30Hz I have MacBook Pro (13-inch, 2018, Four Thunderbolt 3 Ports) with macOS High Sierra installed. I plugged it in to external display: LG 24UD58 24" via DisplayPort through USB-C

For unknown reason Macbook works at 30Hz instead of 60Hz. I managed to achieve 60Hz once somehow by switching between resolutions in Display settings, but I couldn't reproduce this anymore :(





How to achieve 60Hz with external display on Mac?
I had the same issue for a long time. At first, 60Hz worked. Then something happened and I'd only get 30Hz on my 4K Lenovo ThinkVision 27".

I stumbled upon this article and simply went to Display settings and hit "Resolution: Default for display". Immediately the display switched to 60Hz. Then I could reapply my Scaled text size setting and 60Hz remained.

What an unsatisfying fix!