El Capitan on GA-Z170X-UD5 Success

[sfenwick]

Where do you fix these parameters? In the UEFI? Please help !

When you boot from BIOS to the EFI partition on your USB drive, and ou see the Clover icon over a row of drive icons, with a small row of round icons below that, use your right arrow key to move to the third small icon in the bottom row called "Options". PCI Devices is under that. The two items under that are the first two under that, "PCI Ownership" and "PCI Injection".