Many people at the ROG forums are describing the same issues with XMP and any Bios version
I have the exact same issues
Lot# CMK32GX4M2B3000C15
I had success with setting the voltages SA/VCCI/DRAM manually, using XMP does not work in any sort of configuration.
Also i had it stable with manual RAM settings, and this weekend i made the biggest mistake, tried to use the 5-way optimization from AI Suite 3 (just to try)... this sent be back to blackscreen, no post and coldboot erroring out with "Press F1" bla bla bla, even when setting everything back and then manually setting the voltages etc. again.
As of writing this i am running my RAM at stock speeds, till i have time to tinker with Voltages again, or ASUS fixes their botched BIOS
Board: Asus Z270H
CPU: I7-7700K