Thank you for your tips! It looks like a windows update did the trickDo you have the latest BIOS installed on your system ? Did you properly connect all the PCI-e cables to the GPU ? Try to reset and clear all the CMOS/BIOS settings, to default values, if need be. The Latest BIOS version of your Motherboard, is as follows:
Version 7A34vAL1(Beta version), dated 2019-05-21.