If this does not fix boot times, try uninstalling DTS and Sonic sonar apps, reboot and check again. If all fails, running on USB 2 default sound with no drivers for the moment fixes boot issue but is annoying. Reboot after and check if boot times are stable. You will only see a command prompt window but wait a few minutes driver is installing. If you want to reinstall drivers and try them, make sure you only use the official driver from the board maker site (for now at least) using the install.bat (run as admin) and NOT the. Use the driver store cleanup utility Available here and force delete any Realtek SOUND files and a-Volute files. You can use DDU utility and run it for sound drivers available HERE.

Workaround is to remove the driver all together for the moment (USB 2 will kick in). The driver seems to have issues on boot and takes up to 10 seconds to load. It's not bios related but Windows loading related. There is an open ticket Asus about the issue. 2276 (2277) drivers from Realtek for their Z590 boards. Some users have reported that Windows is loading slower because of issues with the new USB.