Strange fluctuating stability issue [solved]

[Aurosonic]

Hey guys. searching for help. I have some issues with system stability which fluctuates from boot to boot. I can pass all possible stress tests one day, and completely fails all the tests on the next day with absolutely same settings.
I'm on Apex XI bios 0231. What could be the issue ? Is it some hidden RTL or other subtimings which trains differ from boot to boot ?

[Aurosonic]

Okay, i’ve solved this problem. The issue was MCH Full chech [auto]. Whenever it’s disabled - my system completely unstable and full ov errors/bsods with kmode exception error. So in auto mode from boot to boot it’s been rather enabled or disabled. When i set it to enable all problems gone and syst3m completely stable*