4K BenQ 3200u Monitor with M1 Mini — unable to display at 3200x1800

[megastuff999]

I have just bought a BenQ 3200u to use with a 16" MBP (Work) and M1 Mini (Personal).

The Intel MBP can scale to 3200x1800 on the BenQ @ 60Hz fine (Catalina)

The M1 only gives me options of full native 3840x2096 or 2560x1440 — nothing in between. Is this a known issue?

 

[senttoschool]

Don't want to hijack your thread. But I'm having a similar issue.

I have a BenQ EL2870U connected to my M1 Air using a HDMI/USB-C 4k@60hz adapter. 4k@30hz works fine. But when I use SwitchResX to force it to 4k@60hz, the monitor loses connection (goes blank) once every 10 minutes or so. Have to unplug/plug to get the image back.

 

[megastuff999]

@senttoschool probably best start a different thread as that is a different problem to what I am seeing. Mine is specifically about viewing a certain resolution on Intel MBP that I can’t attain with M1.

 

[senttoschool]

You might want to download SwitchResX and see if it works.

 

[megastuff999]

@senttoschool yes, you’re probably right. Going to try using the same cable I’m using with the MBP with the M1 just in case too. ??

 

[megastuff999]

Well that was an easy fix! Switched to the USB-C to HDMI cable and I can now also select 3008x1692! I have a HDMI 2.1 cable to I will try — not sure what spec the one in the box is!

 

[PBL_1]

Yes, you get limited scaling options with th HDMI output on the M1 Mac Mini. USB-C gives you 3008x1692, which I find the right scaling for a 32” monitor. I don’t know the reason for this.

 

[megastuff999]

Just for the sake of any future readers, USB-C => Display Port cable also worked fine. Only problem was HDMI => HDMI (tried both 2.0 and 2.1 cables)