So I finally got my native Thunderbolt port working on my Asus Z170-PREMIUM running Presonus Quantum. It was a struggle and yesterday I almost gave up. I tried every setting in bios possible, but actually I did not have to change a single thing from the default settings (bios 3801). The thing I was missing was the motherboard firmware update which is not the same as bios update.
(People that buy the Asus Thunderboltex 3 adapter has to change the settings in bios. I can also connect my motherboard to Asus Thunderboltex 3, but don't see the point since you only are allowed to use one Thunderbolt port at a time cause bios does not allow two.)
I have just tried the Quantum for a couple of hours but it seems stable and fast . See video under
My system:
Hardware:
Asus Z170-PREMIUM motherboard (native Thunderbolt port)
Intel Core i7-6700K Skylake Prosessor
Corsair Vengeance LPX DDR4 2400MHz 32GB
MSI GeForce GTX 1070 TI Gaming 8GB

StarTech THUNDERBOLT CABEL 2M (TBOLTMM2MW)
StarTech THUNDERBOLT 3 TO THUNDERBOLT 2 adapter (TBT3TBTADAP)

Software:
Windows 10 Home latest update
Asus motherboard bios: Z170-PREMIUM-ASUS-3801
Asus motherboard firmware update: FW_update_tool_of_Z170-PREMIUM Important!!!!!!!!
Thunderbolt TM software: TBT_WIN10_64_17.2.71.250
Presonus Quantum driver: PreSonus_Universal_Control_v48221

 

Last edited: Jan 11, 2019