3 ms·

The protocol is great and works just fine. The problem is with the OS you're using. Install Windows on the same machine and it'll work fine.

vladvasiliu 3y ago
Maybe it will, maybe it won't. 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. --- [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.
- ComputerGuru 3y ago
  I was going to say “install Windows or Linux” but decided against including the latter bit because I didn’t have sufficient firsthand knowledge of the hardware compatibility story there. I should have trusted my gut ;)
- p_l 3y ago
  DP sometimes has issues with plug detect on pin 20, using cables with only 19 pins help.
  - vladvasiliu 3y ago
    I don't know how many pins my cable has, and never knew there was any such difference. It's the one that came with the monitor. 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.
    - lostmsu 3y ago
      It is possible GPU just does not sleep on Linux.

vladvasiliu 3y ago

Maybe it will, maybe it won't. 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. --- [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.

ComputerGuru 3y ago
I was going to say “install Windows or Linux” but decided against including the latter bit because I didn’t have sufficient firsthand knowledge of the hardware compatibility story there. I should have trusted my gut ;)
p_l 3y ago
DP sometimes has issues with plug detect on pin 20, using cables with only 19 pins help.
- vladvasiliu 3y ago
  I don't know how many pins my cable has, and never knew there was any such difference. It's the one that came with the monitor. 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.
  - lostmsu 3y ago
    It is possible GPU just does not sleep on Linux.