But it worked perfectly because the two RAM kits were Asus Prime B350M-A compatible and 2400 MHZ DDR4 is a JEDEC standard.even with stock. if the timing is different, it might not work
That's not a valid answer, anyone can say that.that why I said sometime it work, sometime it doesn't.
the data sheet don't test for mixed ram.That's not a valid answer, anyone can say that.
A valid answer would be: I saw the data sheets of the memories and the motherboard so I can say that they are compatible.