IMHO, the SA and DT were spoken to by the PJ in the same manner they spoke to him. When LDB spoke more "gently" he responded in kind - lots of soft laughs and such, for example.
As for the computer make/model - My 15 yo stepson knew exactly which one he wanted as well, and he's no computer pro by a long shot. Most people check out this information so they know how much they need to save to make the purchase. This PJ doesn't seem to have a lot of money, so I think that would be a "normal" bit of info for him to have/need.
Again, my :twocents: with all due respect!