Sharing : Solved M1 limited resolution selection
 

Hi, just to share how I resolve limited resolution selection for M1 MBA

Dock : Dell D3100 (bought USB type B 3.0 to type C)
Monitor Philip 32" 2k display (model forget)

Issue : after install display link manager 1.2, the monitor only limit the max resolution to 2048x1152 which is not usable

Fix : install RDM (https://avi.alkalay.net/software/RDM/) take ur own risk

RDM allow me to select 2560x1440 :D

Just to share, just incase u r nervous after getting your brand new M1 but monitor resolution disappoint you

This worked for me.... I moved from a 2018 MacBook Pro and am using the 6950 Plugable dongle on an OWC dock. M1 doesn't detect 1440p like before, RDM allowed me to bypass and select the desired resolution.

I have more cables and StarTech adapter coming that specifically says "compatible with Mac".... not sure why if it works by manually forcing it with RDM that the native DisplayManager software can't make it work...

Now I just have to figure out why when using DisplayLink monitors, the Music app pauses between every new song...........

This is unfortunately not a solution for me.

I am using a MBP 13" M1 with an LG 32UL950-W 4k 32" display.

The display is connected to the MBP using the StarTech USB32DP24K60 USB 3.0 to Dual DisplayPort DisplayLink adapter.

I am able to select 3840x2160, which is too small for my eyes. Or I can drop it down to 1920x1080.

Typically I would use a HiDPI (scaled) setting of 3008x1692 (which appears when the display is connected directly, not via DisplayLink).

Using RDM, I see the same resolution options as other programs of this type (EasyRes, SwitchRes X). I can select alternative resolutions that aren't shown in the macOS system preferences, but they are NOT HiDPI (scaled), and therefore look very fuzzy (unusable for me).

If this can be corrected via software that would be fantastic.

This is not the most recent version of RDM. The (open source) software was developed further by another developer. Here is the current GutHub Repository with a version with Apple M1/macOS Big Sur support.

https://github.com/usr-sse2/RDM


I did a lot of testing. With RDM 2.5 (see link above) one can create custom resolutions, what would theoretically solve the problem and allow to create a custom HiDPI resolution. This works with the Apple M1 and Big Sur. However, the DisplayLink driver ignores those customizations. I already informed the DisplayLink developer team about this and hope that they fix this soon.

high resolutions
 

I was hoping to run at high resolutions on an M1 Mac, but the SwitchResX person says that, when on HiDPI, it seems to max out at 3008 pixels wide (probably just enough to cover the 6k display in Apple's highest resolution mode.) I currently use 4k (HiDPI) on a 5k iMac, and would like to keep it. Any way this can be done?

DisplayLink Drivers do not support HiDPI above 1920x1080 for a M1 (assuming your using a M1?). This has been an outstanding feature request since last year. You can vote for it here.

In regards to can anything be done to overcome the limitation, the only available solution that I am aware of appears to be to acquire a single monitor with enough real estate space and then drive it directly from the M1. The M1 itself provides HiDPI resolutions above 1920x1080.

Actually, I was hoping to see a HiDPI resolution of 3840x2160 - so internally it's thinking at 7680x4320. Works on my Intel - but seems to be impossible on an M1. Right?

correct. Intel is fine with Displaylink. M1 can not do it with Displaylink.

On other forums, progress is being made on bigger HiDPI resolutions on M1.

SwitchResX enables some resolutions, but nothing greater than x=3737, for some:

https://forums.macrumors.com/threads.../post-30712633

BetterDummy enables pretty much any resolution on a plain M1:

https://github.com/waydabber/BetterDummy/

Disclaimer: I don't have any DisplayLink product to test it on.

This worked! M1 MBPro + DisplayLink 1.6. The virtual display allows me to use HDPI on my 4K monitor (not too small as in 3840x2160 native or too big as in 1920x1080 native.)

Thanks!