Users of M4 Macs report problems with ultra-wide monitors

The Apple M4, which is installed in the new Mac mini, MacBook Pro or iMac, supports up to three external monitors (depending on the Mac), including two with 6K resolution and one with 5K resolution. Alternatively, an 8K screen can be operated at 60 Hz or a 4K monitor at 240 Hz. However, the chip has problems with certain monitors, as user reports on Reddit and the Apple Community Forum show.

Specifically, 5K monitors in 21:9 format cause problems, i.e., screens with a resolution of 5,120 x 2,160. While the screens can be used at full resolution without issue, the "HiDPI" mode cannot be activated. In this mode, a resolution of 3,840 x 1,620 is scaled to the native resolution of the monitor without loss of sharpness. According to affected users, the same monitors function just fine when connected to olders Mac with an ARM or Intel chip using the same cable. 

Some users have been able to solve this issue with third-party apps such as BetterDisplay, but with the frame rate restricted to 60 Hz. Apple is yet to comment on the matter, so it is unclear whether the company is currently working on a solution. Those who have a M4 Mac and a 5K x 2K display will simply have to wait and see, as solutions such as BetterDisplay, SwitchRes X and EasyRes do indeed allow users to set different resolutions, but at the expense of the frame rate or image quality.