I'm always impressed by how well designed Display-Port is, as a connector and as a protocol.
DDC is also fraught with peril when you want to change settings from OS on non-Apple display.
I'm not sure if it's intentional, but it is at least giving an image.
It’s really irritating, as we bought these displays specifically because the previous Dell displays didn’t work well with Macs.
I never isolated it because I hadn’t been to that office for 4-5 months during the pandemic. It’s also miserable as the logging for this stuff sucks and nobody really understands how this stuff works. One of my colleagues had success with a thunderbolt dock.
Do they behave any better if you only have one plugged in at a time? MacOS seems to have problems with multiple identical displays.
My HP laptop with integrated Intel graphics and an HP USB-C dock would have me do a dance of unplugging and replugging the DP monitor at the right time to get 4k@60Hz under Windows. No, plugging it while the PC was running didn't work; for some reason, it was the unplug/replug action which did the trick.
Worked perfectly fine under Linux. Then a Windows or Intel driver update mostly fixed it. Now I "only" get weird "out of range" or a garbled screen when waking from sleep sometimes [0], which usually goes away by switching inputs back and forth on the monitor. Still works fine under Linux.
On the other hand, HDMI via the same dock gives weird-looking colors under Windows, but it always worked at 4k@60. Because of the colors, I never actually used it, so I don't know if it survived a sleep/wake cycle. Never bothered to try HDMI under Linux, though.
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[0] It seems related to how long the PC has been sleeping. If it's only a few minutes, it's OK (say going to the bathroom or similar - default windows settings are quite aggressive for putting the pc to sleep). But if it's longer, like an hour or so, I'd say it's 50-50 whether the screen works properly.
I chalked it up to a driver issue, since the exact same hardware works great on Linux.
I also have a separate, random Chinese dock off Amazon, which I couldn't get to work under Windows with that particular laptop. It works fine under Linux on that same laptop, and also works fine under Windows with a different, AMD-based laptop.
I haven't tried it in a while, but right after it started working with the HP dock, this particular dock was still not working at all.
Whoever thought of the locking mechanism on them can, sincerely, die in a fire.
Bloody things cause me more grief than the weeds in my garden.