Intel 9 285K on ASUS Z890: not stable!

Update (2025-05-15): Turns out the CPU was faulty! See My 2025 high-end Linux PC for a new article on this build, now with a working CPU. Update (2025-09-07): The replacement CPU also died and I have given up on Intel. See Bye Intel, hi AMD! for more details on the AMD 9950X3D.