XMP is somekind of overclocking, but I disabled it.
Its not only one bit flip but at leats two (in a single byte), I figured out using addresses in the errors.
I was also scared that it's the cpu, because it was the most expensive part when I build the PC. Thankfully I think it's not, now I'm running memtest again with no errors without one ram stick.
I disabled XMP (overclocking, but not really) and still errors. I removed one stick and the test is currently on 35% with no errors (thats new record). I will also try with other one to confirm its defective. Thank you :)
Medicat is like a Ventoy (USB that can have multiple iso files).
Now I disabled XMP (makes ram faster) and ran test again and still errors. I noticed that all errors give same mesaage: expected "address", actual "wrong address" and wrong address is the same as expected address but 1 byte different. For example expected is FFFFFFF7, actual is FFFDFFF7. And this error is always on CPU core 6.
I have 2x 16gb of ram, so I will try test again with only one stick and then with other one.
I'm sure it will be and I'm also sure Apple will do EVERYTHING to make it almost imposible to do that. They may also block users from using their iPhones if they discover that they are set to EU, but they are actually not in EU.
I've used it a few times and it's great!