PCI�s Origins and Competitors

PCI started as an industry initiative that aimed to overcome the limitations of the then-current PC bus (ISA bus). Initially proposed by Intel, it was developed by a group that included systems manufacturers, component vendors, suppliers of add-in cards and peripherals, and software companies.

Competition for the bus at the time included IBM�s MicroChannel Architecture (MCA), introduced on their PS/2 personal computer systems and the EISA bus, promulgated by a PC manufacturers� group.

MCA, unlike the open ISA bus, was a protected piece of IBM intellectual property; the result was that it only ever appeared in IBM products.

EISA suffered from a different problem; since it was backwards compatible with the venerable ISA bus, it embodied a number of compromises which limited its advantages over the earlier standard.

PCI won against both MCA and EISA through its combination of functionality and its openness.

Source of Information : Elsevier Server Architectures 2005