To add on this, playing a very low intelligence character in the old Fallout is really an experience to try.
From the start you can even feel the despair of your tribe shaman that send you to get the item that should save your tribe, knowing they're probably all doomed because there's no way you'll get things done
But in the same time it's much much harder too as most NPC that could be usefull in normal condition will not help/join (as most of the NPC will treat you like crap, showing their true color and most will enjoy to just humiliate you) and the majority of quests will become impossible to obtain or complete (some towns become useless for your character as you will have nothing to do) because your character is too stupid to figure out some basic stuff required.
A good tip would be to always have those pills that increase temporarly your intelligence when you need to talk to one of the quest giver, but doing so also defeat the point of playing a low intelligence character. You can always try to take revenge on every NPC that humiliate you , but that's going to be a long list of people that will get hostile to you once you start killing.
I wonder if the game storyline is actually completable with such character as i never went past mid-game myself with that kind of build (as the too few quests that are possible with low intelligence to obtain made the game a bit too flat).