I have a Mini-ITX board, I noticed that if I activate XMP, the board will cease to work, but it works with 4 GiB of RAM at standard frequency.
So it seems memory is a general problem among Mini-ITX boards? Perhaps the reason is that these boards have less available space for routing, fewer layers, and targets a lower price, so they trend to have worse electrical characteristics?
Quality of the PCB and the number of layers definitely plays a factor I'm sure it isn't limited to ITX though. I have noticed compatible differences between super robust Intel ITX boards vs ECS thin and wobbly ITX boards, with the ECS board having more issues, quirks and what not.
