10. And you can get figures that raise all your stats by 1, and you can use chems that raise them up to 4, and several other ways besides. HOWEVER, power armor only raise your stats by 2 strength, but lowers your agility by 2. Which is stupid of course, as this negates the whole concept of power armor.
They say in the game that the Enclave's armour is better, BOS soldiers talk about this all the time, but those armors only give you +1 str and -1 agi, or nothing at all - and they do not have significantly higher damage reduction. Bah.
And don't let me start on the stupid tesla armor..