Apple transitioned the CPUs of their Mac and Xserve computers from PowerPC to the x86 architecture from Intel.

The change was announced at the 2005 Worldwide Developers Conference (WWDC) by then-Apple CEO Steve Jobs, who said Apple would gradually stop using PowerPC microprocessors supplied by Freescale (formerly Motorola) and IBM.

This was the second time Apple changed the processor instruction set architecture of its personal computers. The first was in 1994, when Apple discarded the Mac's original Motorola 68000 series architecture in favor of the then-new PowerPC platform.

Apple's initial press release said the move would begin by June 2006 and finish by early 2008, but it actually proceeded much more quickly. The first-generation Intel-based Macintoshes were released in January 2006 with Mac OS X 10.4.4 Tiger. In August, Jobs announced the last models to switch, with the Mac Pro available immediately and the Intel Xserve available by October (it actually shipped in December).

The final version of Apple's Mac OS X that ran on PowerPC chips was 2007's Leopard (version 10.5), released in October 2007. The final version to run applications written for PowerPC chips, using the Rosetta binary translator, was 2009's Snow Leopard (version 10.6). Mac OS X Lion (version 10.7) dropped support altogether.

In 2020, Apple announced that it would shift its Mac line to Apple silicon, which are ARM-based processors developed in-house.