Abstract: An .times.86 based computer system that implements a firmware based boot process without an .times.86 BIOS that supports expansion devices coupled to the computer system, wherein the expansion devices include their own respective BIOS extensions. The computer system includes an .times.86 processor coupled to a volatile memory and a non-volatile memory via a bus. The non-volatile memory includes firmware which when executed by the processor cause the computer system to implement the boot process. The firmware initializes device drivers for the computer system and initializes an application programming interface for the device drivers. The firmware then initializes a compatibility component for interfacing with the device drivers, wherein the compatibility component is operable for translating accesses by a first software application to an .times.86 BIOS into corresponding accesses to the device drivers.