Apple-Intel architecture

The Apple–Intel architecture, or Mactel, is an unofficial name used for Apple Macintosh personal computers developed and manufactured by Apple Inc. that use Intel x86 processors, rather than the PowerPC and Motorola 68000 ("68k") series processors used in their predecessors. With the change in architecture, a change in firmware became necessary; Apple selected the Intel-designed Extensible Firmware Interface (EFI) as its comparable component to the Open Firmware used on its PowerPC architectures, and as the firmware-based replacement for the PC BIOS from Intel. With the change in processor architecture to x86 Macs gained the ability to boot into non-Apple operating systems, while Intel VT-x brought near-native virtualization with OS X as host OS.

Apple–Intel architecture (Mactel) is an unofficial name used for Apple Macintosh personal computers developed and manufactured by Apple Inc. that use Intel x86 processors. As the name implies, it refers to changes in the architecture from the earlier PowerPC, Apple 68k, and other preceding processors.

Apple uses a subset of the standard PC architecture, which provides support for Mac OS X and support for other operating systems. Hardware and firmware components that must be supported to run an operating system on Apple-Intel hardware include the Extensible Firmware Interface.

With the change in architecture, a change in firmware became necessary.Extensible Firmware Interface (EFI) is the firmware-based replacement for the PC BIOS from Intel. Designed by Intel, it was chosen by Apple to replace Open Firmware, used on PowerPC architectures. Since many operating systems, such as Windows XP and many versions of Windows Vista, are incompatible with EFI, Apple has released a firmware upgrade with a compatibility support module that provides a subset of traditional BIOS support with their Boot Camp product.

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