I want to set up HIDPI on my second monitor. My first monitor is connected directly to the Mac (M1) and works fine with HIDPI. Second monitor is connected through dock (Stoltzen DL-Dock pro) with Displayport cable.

Hello, I'm having the same issue here with my Macbook Air M1, I have two 2K Dell monitors connected and since the MBA M1 only supports one display, I have to connect the second via a Dock that supports DisplayLink, I'm using the Dell D6000

If the monitor is connected to usb-c, BetterDisplay allows me to activate the High Resolution (HiDPI) option but not when the monitor is connected to the Dock

The information here may be helpful --> https://support.displaylink.com/know...al-hidpi-modes

I’ve already tried that, but it had no effect. I have two Dell G2724D monitors: the one connected via USB-C is crystal clear, while the other, connected through the DisplayLink dock (Dell D6000), is blurry. I also tried setting up a virtual display in BetterDisplay, as others suggested, but it’s still blurry. It’s a little better, but still far from the clarity of the one connected directly via USB-C.

I’m having similar issues:
I have 3 external 4k monitors that are identical, all plugged in through DisplayLink Dock:
1st Monitor — HDMI — works fine, super sharp at 1440p scaled. Detected resolution 4k.
2nd & 3rd Monitor — DP — blurry. Looks like the monitor is trying to scale 1440p to 2160p. Detected resolution 1440p.

BetterDisplay’s dummy workaround works better, 4k detected, but not as sharp/clear as the HDMI connection through DisplayLink.