IBM's attempt to combat the PC clone market. These machines had many technological advantages over the competition, such as the Micro Channel bus, which was the first PnP and local bus to be found in a consumer machine. Sold poorly except to busines customers who could afford to shell out the big bucks for these machines. Their bus made upgrades limited and expensive which made a PS/2 an expensive machine to keep up to date. Speeds ranged from the model 25 which is an 8086 to the 95 which can take up to a pentium 66 cpu. Eventually IBM gave up their MCA bus on the lower end machines, and offered lower priced models with ISA bus to compete with Compaq's lower priced models.