I read Peter Norton's Inside the IBM PC (1986 edition) [1] a while back, out of an interest in computer history. It struck me as being quite a bit different than today's technical books. It had a very conversational writing style, and it seemed like it was aiming to accommodate computer hobbyists/enthusiasts who wanted to learn more about how their machine actually worked. There were probably a lot more such people back in the 80's than today.