2560x1440 on 4K monitor missing

[phzfn]

Hi,

this is the exact same issue as described here.

https://displaylink.org/forum/showthread.php?t=67397

Just tried it with newest software, still does not work.

Pleas fix this.

[thysm00]

I just purchased a 200$ startech Dual DisplayPort for my M1 Mac mini (on Monterey last version) because I own two 4K dell that only have display port (it also has hdmi 1 but it will only support 30hz and it's really horrible to work with such a refresh rate).

And I have the same problem as the other used on this thread, it will support 2560x1440, but only in "low resolution" which again looks really bad...
These screens work just fine if I use them one by one using a on 2560x1440, so I don't understand why this is an issue... It seems to support all of the other resolutions in both low and high resolution, only this one is not listed...

I hope something can be done about this because 200$ for a huge UI or letters so small I can't read anything is a bit much And I only have like 10 days to return it...

[tommiy]

I think your waiting for HiDPI in other resolutions to be made by displaylink. Its been a request that started 9 months ago. Use better dummy as it fixes the issue for most.

[thysm00]

Originally Posted by tommiy

I think your waiting for HiDPI in other resolutions to be made by displaylink. Its been a request that started 9 months ago. Use better dummy as it fixes the issue for most.

I tried it and it does not work for me... it really looks like i'll have to just send it back... that's too bad, i really thought this could fix my dual display issue, and i can't believe this is not advertised...

[Josasp]

Originally Posted by thysm00

I tried it and it does not work for me... it really looks like i'll have to just send it back... that's too bad, i really thought this could fix my dual display issue, and i can't believe this is not advertised...

BetterDummy works, but you have to fiddle with it a bit.

You create a dummy 4K display, set the resolution on that one to 2560x1440 HiDPI.
Then set your real display to 3840x2160.
Then you set the dummy to mirror onto you real display, then it works.

Last you attach that virtual display to you real display in BetterDummy, and it should survive reboots etc.

It's not perfect, you get few ms delay with mirroring, and also the display gets ever so slightly softer. But you do get HiDPI 2560x1440 on your monitor. It also consumes CPU, It's the only solution at the moment.

The only thing that works "better" than dummy is if you have a MacBook and use the internal display instead of a dummy and use RDM to create 2560x1440 HiDPI custom resolution for the internal display, keep the lid open then mirror that onto the real display.

For some reason the performance on using the internal display is better than dummy.

I have Samsung montiors and MacBook so I've set it up to mirror with lid open, works fine. And low-res 2560x1440 with lid closed, then use Samsung Magic Upscale Mode 2 on the monitor, not HiDPI but looks way better than just normal low res.

So when I want full performance, I just close the lid.

The email notification thing on new DisplayLink drivers doesn't work, I've set up Distill Web Monitor in Chrome on that page, so I get a notification when there's a new driver.

[JanB]

If you try BetterDummy, then try FullScreen-Straeming instead of Mirroring.

I have found that the rendering quality in streaming mode is better than mirroring.