Yes, confirmed - swapping the motherboard has solved thunderbolt issues.
XPS 13 9300 + latest BIOS 1.3 + CalDigit TS3 Plus Thunderbolt 3 dock = works fine under Ubuntu 20.04
Glad to hear this!
I'm waiting for my own replacement to occur, but DELL seems to have a few supply issues in the UK, so hopefully by the end of the month, after 6 months of DELL support beating around the bush, I should be able to enjoy a computer that works. I'll report back.
Update:Running BIOS 1.4.1 now.. no issues with Thunderbolt3 since after the motherboard has been replaced.
Same here, motherboard replaced and now it works with 1.4.1, wasn't working before with the same BIOS version.
I have had a MB swap too and it fixed my USB-C docking station problems. However, I just bought a Caldigit TS3 plus, and while it works well on Windows, it is not the case on Linux.
Can I ask you which model you have? (4k display? 32GB RAM?)