You can't blame someone for being passionate and knowledgeable. Their work is exciting.
Rarely do they gloat. The reason they talk so much is because their subject makes them happy. They know it and out, spent countless hours studying and missing out on meals and sleep. But they still have crazy energy.
I don't know about you but these “nerds” are the type of people I like to work with. It's far better than a person that talks a lot for the sake of talking with no insight whatsoever. Those are the fakes.