I'm currently building a ITX system with the above motherboard and a 7700x. The board has two m.2 slots which supports two fourth gen ssds or one fifth gen and one fourth gen. The fifth Gen is on the front only with available fan and the second port is on the back side of the board. My question is, is it ok to use the back side m.2 slot for OS? There is no access once the board is mounted. I'm saving for a second m.2 which will be used for storage and can be mounted on front. I do not plan on using fifth gen m.2