I'm just going to park this here for anyone who has run into the same frustrations I have with Windows and Thunderbolt. I have 2 Apple Studio Displays and a current generation Ryzen processor with Thunderbolt compatible motherboard. Theoretically it should work, but I have had nothing but trouble, at one point just going back to regular monitors because I was done troubleshooting for hours. In the end, I actually did get it to finally work in a way that is sustainable and allows me to use the monitors in full 5K resolution (though the cameras and speakers aren't working - I'm prepared to make that sacrifice).
I know that I'm an edge case user, most people don't utilize 2 Apple Studio Displays on a Windows machine. But if you happen to be an edge case like me, here's how I solved it:
Attempt 1: Asus ThunderboltEX 4 card connected into nVidia GeForce 3060 RTX card via DisplayPort card. Then 2 Thunderbolt 4 cables from the Thunderbolt card to the Apple displays. These would work on and off, with a restart or moving the monitors often causing problems and leading to hours of work. Ultimately it wasn't sustainable.
Attempt 2: Upgrade the cables - now it's 2 8K DisplayPort to mini DisplayPort cables going from the GeForce card and then 2 upgraded 8K capable bidirectional Thunderbolt 4 cables to the monitors. Same result.
Attempt 3: Skip the Thunderbolt card all together, utilize 2 DisplayPort to USB-C cables that are designed primarily for VR headsets. Same result.
Attempt 4: Update motherboard drivers, update Thunderbolt drivers, go back to the 8K cabling. Same result.
Attempt 5: Get frustrated and call it a day. Live with other monitors.
Attempt 6: Figure out that there's one other option and connect the Thunderbolt card to the GeForce via the 8K DisplayPort cables. Connect the ThunderboltEX 4 card to a QGEEM Thunderbolt Hub. Connect the 2 monitors to the Thunderbolt hub. Rejoice because for the first time it is working without worrying that if you touch it or look at it wrong, it will suddenly turn off.
