I also noticed that under Profiles > Computer > Displays there are 4 different 'LG HDR 5k' entries. Header message digest (MD5) is not correct.

System/Library/ColorSync/Profiles/ITU-2020.icc I think that started with the Catalina update.Īfter reading Incorrect external monitor resolution detected, true resolution not available I went into the Color Sync Utility and Verify found one issue, but Repair couldn't fix it: Searching for profiles. It also sometimes turns on HDR mode when using the wrong resolution, which just has the effect of making everything a little darker. I'm currently on macOS Catalina 10.15.4, but this also happened on previous versions, including Mojave releases. Resolution: 3440 x 1440 (UWQHD - Ultra-Wide Quad HD)įramebuffer Depth: 30-Bit Color (ARGB2101010) > Graphics/Displays, it has the display connected to the Radeon Pro 550X with the following info: LG HDR 5K: It also forgets the arrangement of the display relative to my MacBook's screen when using the wrong resolution it remembers when it uses the correct resolution. I mainly use the ThunderBolt 3 cable that came with the monitor, but I also tried a short passive TB3 cable - same results. (To reboot the monitor, I just unplug it from the wall, wait a few seconds, then plug it back in.) Sometimes disconnecting and reconnecting the cable fixes it, sometimes switching to a different TB3 port in the MacBook fixes it, sometimes rebooting the MacBook or the monitor fixes it, but nothing reliably fixes it, and sometimes I go through all of the above and still have the wrong resolution. This makes me suspect it's using DisplayPort 1.2 instead of 1.4, because I believe that's the maximum resolution DP 1.2 supports. When this happens, the MacBook doesn't even give me the option of using the correct resolution in system preferences - even if I Option-click on Scaled, the highest resolution available is 3840x2160. But, sometimes when I connect my MacBook (via ThunberBolt 3) or when it wakes from sleep already connected, it sends a 3440x1440 image to the monitor, which looks fuzzy and gets a warning from the monitor about the incorrect resolution. The correct resolution of the monitor is 5120x2160 and sometimes everything works at that resolution. I have a 15' 2019 MacBook Pro and a LG 34BK95U monitor (business version of 34WK95U - same hardware, longer warranty).

3440x1440p f1 2019