That's literally the same experience I have with the MSI TB3 card. You were talking about the ASUS one, I guess?

The level of BIOS bugginess on recent motherboards is reaching astronomic levels. The MSI motherboard I was trying that on will literally _duplicate_ the entire ACPI DSDT whenever you enable TBT (Linux shows a hundred warnings when booting up, which MSI claims is fine)...

it's too bad AMD doesn't have first class TB4 support yet, at least not on the consumer hardware i've been looking at

> Just FYI for anyone tempted to buy this card: it does not work. There are multiple revisions and none of them work right.

Ah, the ASMedia experience! Glad AMD picked such an experienced and well-regarded company to do their chipsets /s

edit: Okay, the linked part actually uses an Intel chip, though the point still stands. ASMedia has so many other chips and bridges (including the mentioned AMD chipsets) and they're all pretty notorious for weird "huh that was supposed to work" kind of problems. Problems that generally don't happen on Intel platforms.

The fractal brokenness of the Thunderbolt ecosystem in Windows is... something. I was hoping that USB4 would at least make it a little nicer by confining failure modes to PCIe not working while the USB tree worked as normal since the USB tree was native, but my Asus motherboard with built-in USB4 not infrequently manages to get itself into a state where DisplayPort and downstream PCIe devices work while USB devices plugged into a USB4 hub don't.

(also an older Asus with its TB3 expansion card only worked at all in Windows if you disabled the "enable Windows support" option in the BIOS, which is an interesting choice)