I’m experiencing an issue with my portable monitor when connected to my desktop computer (portable mini PC) running Manjaro.
The monitor works perfectly on both Windows and macOS machines, using the same Thunderbolt/USB-C cable. However, on Linux, whenever I set the monitor’s brightness above 90%, it starts flashing and making strange noises. This problem disappears when I connect the monitor to an external power source, in addition to the connection to my computer.
OS: Manjaro Linux x86_64
Kernel: 6.6.19-1-MANJARO
Plasma 5.27.11
lspci | grep -iE 'thunderbolt|usb-c|usb4'
00:03.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 19h USB4/Thunderbolt PCIe tunnel
00:04.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 19h USB4/Thunderbolt PCIe tunnel
c6:00.5 USB controller: Advanced Micro Devices, Inc. [AMD] Pink Sardine USB4/Thunderbolt NHI controller #1
c6:00.6 USB controller: Advanced Micro Devices, Inc. [AMD] Pink Sardine USB4/Thunderbolt NHI controller #2
I’d guess that you have three separate machines. Certainly, it seems unlikely that Windows/MacOS and Manjaro are on the same machine. If so, the most likely explanation is that your MiniPC can’t supply as much power out of it’s USB-C port as the other two, and therefore needs the external power source.
So likely not a Linux issue, but a hardware issue.
When you say the problem disappears with the above action - my immediate fhought is grounding.
The mini-pc may lack the proper grounding or isolation and the higher the throughput in the USB power/data cable - the more power is consumed - and due to improper isolating or grounding of the USB-C port you get the noise and flickering.
This is not a Manjaro or kernel issue but isolated to the mini pc’s hardware.
You have twothree options
take the mini-pc apart and fix it - it could be a flaky soldering point
if still under warrenty take it to shop where you bought it
consult a electronics hardware specialist to fix it
I apologize for the inaccuracy; it’s about three machines: my son’s computer with Windows, my MacBook Pro, and a MiniPC with Linux (my main development computer).
Thank you very much for the advice, guys, I thought it would be a hardware problem. After all, I’ll just have one more cable.
To quickly answer the aside, to the best of my knowledge neither Windows nor Manjaro run natively on current Mac hardware, so multi-booting Manjaro with Mac seems unlikely. Yes, there are older Intel Mac’s out there, but that’s why I specified “unlikely” rather than “impossible”.
Well, I don’t have M3 to play with; though with Intel hardware, more is possible with multibooting than I’d have anticipated just a few years ago. All three of the major food groups are coexisting nicely on one of my recent machines. However, it can occasionally take some dedication to keep the status quo. Cheers.
