Maybe this question in strange anyway ... my iMac 27" has max resolution 5120 x 2880, it is 5K retina display (photo 001), but why in display settings max resolution allowed is 3200 x 1800 ? (photo 002).
Thanks.
iMac 27″ 5K, 11.1
Likely because that is the resolution you selected. Please refer to https://support.apple.com/guide/mac-help/change-your-displays-resolution-mchl86d72b76/mac to learn how to change it back to the default setting.
But there are no others choices ... the max resolution that I can choose is 3200 x 1800 .
iMac 27" Retina 5K (2017) resolution
