Even the guy who "successfully" installed Win7 on the board had to use a PCIe USB card, PS2 Keyboard and mouse, and couldn't get the MB USB ports to work.

i manage to get windows 7 x64bit correctly installed and fully working on my Asus Maximus XI Hero Z390 , it's a painful slow process but it works 100% for me. You will need a pci-e to usb expansion card with at least 2 usb ports , a native PS2 mouse and a native PS2 keyboard. You will need to use some software to do this = ASUS EZ Installer ( download from the Asus Strix Z370 support page ) - https://www.asus.com/Motherboards/RO...Desk_Download/ , Gigabyte Windows USB Installation Tool ( download from the Gigabyte Aorus Ultra gaming Z370 support page ) - https://www.gigabyte.com/Motherboard...ort-dl-utility follow the instructions on this video - https://www.youtube.com/watch?v=APcboOpP4TY and this https://www.youtube.com/watch?time_c...&v=8VTC4k6SLWY. A windows 7 x64bit usb installation flash drive , Rufus. ** Follow the videos and also you need to inject those asus drivers , eg. you need to use both utilities Gigabyte and Asus to inject all the drivers to be able to install windows 7.

After you finally install windows 7 , install the drivers for your pci-e to usb expansion card with your PS2 mouse from other HD OS installation and that's it a fully working windows 7 x64bit , now you can use those 2 usb ports to use your usb keyboard and usb mouse * Go rip some benchmarks on windows 7 for hwbot , remember to save yourself an image with acronis or other software for re-installation if you ever need to re-install windows 7 again. , back up OS save image.

Important note * The usb ports of the Z390 motherboards do not have windows 7 support eg. No drivers exist for windows 7 , only windows 10 as this is a brand new chipset with all the usb included on that new intel Z390 chipset , blame microsoft and Intel for this end of support of windows 7.