Going down in size we have a mini ITX motherboard with a maximum size of 6.7″ x 6.7″ (17cm x 17cm). Notice that there is a single expansion slot and the motherboard itself is considerably smaller than the ATX and even the micro ATX. Also notice that the faceplate still line up and the hole positions still match the ATX hole positions. Theoretically we could take this micro ITX motherboard and place it inside a full tower case. However we usually use a small form factor case for this motherboard.