dell monitor u2720Q on mac studio m1 ultra

Have a look at the following "Dell Display and Peripheral Manager for Mac" guide.

see > https://dl.dell.com/content/manual11765345-dell-display-and-peripheral-manager-on-mac-user-s-guide.pdf?language=en-us

If that doesn't help, then reach out directly to Dell for "Management Software" support.

see > https://www.dell.com/support/home/en-us

Thanks... I'm at a loss though I wonder if it requires HDMI, I've read that some other Monitors require that for back & forth communication...

If Dell Display and Peripheral Manager cannot identify or establish communication

with a compatible Dell monitor or webcam, follow these steps to troubleshoot:

1. DDPM will not work if the external monitor is set to Use as Mirror for Builtin Retina Display. Change the Display settings to set external monitor to Use

as either Main Display or Extended display.

Display Settings is available at Apple menu > System Preferences > Displays.

2. If connecting HDMI cable not working, switch to use HDMI and USB upstream

cable. Launch DDPM again.

3. Check the monitor OSD to ensure DDC/CI is enabled.

4. Remove any docking stations or cable extenders or converters between the

monitor and the graphics port. Some low-cost extenders, hubs or converters

may not support DDC/CI properly and can fail Dell Display and Peripheral

Manager. Update the driver of such device if the latest version is available.

5. Check if the webcam is detected under USB section in System Information

6. Wait for a few seconds after unplugging the webcam before re-connecting it

to the computer.

7. Restart your system.

https://dl.dell.com/content/manual11765345-dell-display-and-peripheral-manager-on-mac-user-s-guide.pdf?language=en-us

Un-encumbered by knowing ANYTHING about Dell Display Manager, I can say with authority that the vast majority of display users on Macs never install and use such software.

If it never works, what features do you lose that cannot be attained by other means?

Grant Bennet-Alder wrote:

Un-encumbered by knowing ANYTHING about Dell Display Manager, I can say with authority that the vast majority of display users on Macs never install and use such software.

I'm using a Dell monitor that supports it – but I never installed that software.

If it never works, what features do you lose that cannot be attained by other means?

Dell is apparently now calling the Mac version "Dell Display and Peripheral Manager for macOS."

Dell Support – What Is Dell Display Manager?

Dell Support – Dell Display and Peripheral Manager for macOS

How is is connected?