Hi STARRAIN,
Update test result.
Test bios : 2201
Bios setting : DOCP disable, PBO disable, PCIEX16_1 GEN3, M.2_1 GEN3, Resizable Bar disable, IOMMU disable, C-State disable.
Test Phone : iPhone 12 PRO
Procedure :
Update bios by using USB dongle from bios flashback
Power off and unplug PC from power-plug
Power on after 3 minutes.
Change bios setting and boot into Windows10 21H1
Plug USB port back of PC (USB3.1 type A)
Disable all other Internet interface
Enable mobile hotspot on iphone
Run Speedtest via browser
After running speedtest client, it would be no connection in few seconds, and show "download test error" message, but my phone can still surf the internet .
Run Windows Network Diagnostics, and still shows "The default gateway is not available"
Repair interface and checked again with other port, no connection still occurred after running (large) packets.
I also checked Apple Mobile Device Service(AMDS)and device driver with my other PC, but it seems the same.
Should it be SW issue, MB issue or some errors with my Ryzen 3700x? I have no idea about it but still need to repair it...
Regards,
Supplement,
Wi-Fi via phone is stable and there is no issue on it.
External hard drive and VR device has no issue after check