Wait, HWinfo64 shows 2 "CPU" errors?
I'm still betting on overclock being unstable.
Pretty sure your ram is dodgy, unsure why the memtest you did was fine if that's the case though.
download hci mem test from:
https://hcidesign.com/memtest/
Open the test and run it, and keep doing this process until you've used up 90% of your ram, Check task manager for % used.
Leave it running for a while, 100% is the basic pass, going over will help confirm for sure if it's stable or not.
That's it for the ram.
Now for the CPU
Download "Realbench" from asus, and do the stress test, it's 15 min test by default, it's harder than AIDA which is a joke to run, so the stress / heat caused is higher, Again, have HWInfo open and keep an eye on temps but also the error log at the bottom.
I'm betting the pc will crash/bluescreen, I think the mem test will find the errors because a cpu instability normally just crashes the pc not the programs.