I'm Using X670E-F with latest BIOS (which is 1415) also got random reboots, not frequent but still have random reboot, MCR Disable, PBO enable With per core -20 and (most usage core set to -10) , power down disable, Wait 3 second to 4 second, Boost O...

you can disable Armoury crate auto-install by disabling it in the bios