Are two RAM slots enough for 32GB on a mini-ITX board?

Yes. Two 16GB sticks give you 32GB, and that setup is standard on most mini-ITX boards. Confirm your motherboard and CPU support 16GB per slot—almost any board from the last five years does. Two slots mean no room for future upgrades, but 32GB is plenty for gaming and most work. Just don’t buy super sketchy RAM.