IBM put 12 Engineers in a room down in Boca Raton and told them to come up with a personal computer - That was in August, 1981. I believe if I remember right that none of the parts were made by IBM, it was just assembled with all parts bought - I could be wrong, but that is how I remember it - Click on the link below to read more about that big life changing invention:
http://www.informationweek.com/byte/news/personal-tech/desktop-pc/231002983 (http://www.informationweek.com/byte/news/personal-tech/desktop-pc/231002983)