BIOS is dead! Long Live UEFI!

At EMEA 2011, Mike Meyers spoke to a group of technologists on an upcoming transition that many are not aware of: the change of standard boot firmware from BIOS to UEFI.

Meyers began by describing the origins of Basic Input/Output System (BIOS) on CP/M systems in 1980. Matching the hardware of the time, BIOS was 16-bit code, and as systems advanced to 32 bit and eventually 64 bit, BIOS was the last remaining 16-bit code on systems. This limited the functionality of BIOS, and operating systems began taking on functions that would more naturally reside in firmware. In addition, BIOS was tied to the master boot record as the boot sector, which supports hard drives as large as 2.2 TB.

UEFI was introduced in 1995 with Intel Itanium processors. Simply from a desire to run all code at 64 bits, engineers designed a replacement for BIOS called Extensible Firmware Language (EFI), which later evolved into Unified Extensible Firmware Language (UEFI). This provided much greater functionality—one could now boot the system and perform many functions without ever entering an operating system—but without a technical reason for moving away from BIOS, motherboard manufacturers were reluctant to adopt the new firmware.

The tipping point came in early 2011 with the introduction of 3-TB hard drives in the consumer space. These drives now exceeded the limits imposed by the master boot record, so drives had to be split into separate partitions. Many tech-savvy consumers create partitions on their hard drives for various purposes, but it is too awkward to be a solution for the general public. Motherboard manufacturers began the transition to UEFI in earnest, and soon all computers will be run on UEFI.

For the average consumer, this change will be transparent since they had little need of ever entering the firmware of their machine. For computer technicians, it is an important change. Not only will they have a new format to learn, but the expanded functionality of UEFI opens the door for new functions in diagnostics and testing. The user interface for UEFI is also greatly improved, which will help techs feel that they have entered the modern age when dealing with firmware.

It will be interesting to see what types of diagnostic capabilities come forth from UEFI. The attendees at the EMEA session were clearly engaged in Meyer’s presentation and demo and were interested in the inner workings of this new format.