The latest episode of ATP included a discussion about MacOS 27 dropping support for Intel Macs and MacOS 28 (partially?) dropping support for running intel binaries. I have been curious about this, so did some Wikipedia diving and put this post together.
68K to PPC
The first 68K Mac was the original Macintosh 128K in January 1984. The last 68K Mac to be introduced was released in August 1995.
The first PPC machine was released in March 1994
The last MacOS to support 68k processor was MacOS 8.1. MacOS 8.5 which did not support 68k Macs was released in October 1998.
PPC Macs included a 68K emulator. Initially large parts of MacOS (or System 7 as it then was) remained 68K and was emulated on all PPC Macs. Over time more of MacOS was converted to PPC. The 68K emulator existed as long as the Classic MacOS survived, and continued to exist as part of the Classic environment in MacOSX. The Classic environment was discontinued with Mac OS X 10.5 Leopard, which was released in October 2007′
PPC to Intel
The last PPC mac released was a Power Mac G5 in November 2005
The first Intel macs were released in January 2006.
The last MacOSX to support PPC Macs was MacOSX 10.5 Leopard. MacOS 10.6 Snow Leopard, which did not support PPC Macs was released in August 2009
Intel Macs included a PPC emulator called Rosetta. It effectively emulated 32 bit PPC binaries, but did not emulate binaries tuned to the 64 bit G5. The last version of MacOSX to support Rosetta was also MacOS X Snow Leopard. MacOS X Lion, which did not include Rosetta was released in July 2011.
Intel 32bit to 64bit
A far less significant processor transition was the Intel transition from 32 bit to 64 bit. While PPC Macs went through a transition from 32 to 64 bit with the G5 being 64 bit, PPC macs did not exist long enough beyond that point for the 32 bit PPC macs to be phased out. The first Intel Macs ran on 32 bit Core processors, however these were swiftly replaced by of 64 bit Core 2 processors. All subsequent Intel Macs were 64 bit.
Those original 32 bit Intel Macs had a relatively short period of support with none of them being able to officially run MacOS after MacOS X 10.6 Snow Leopard. 32 bit Intel software continued to be supported in MacOS until macOS Mojave. MacOS Catalina released in October 2019 did not support 32 bit Intel software.
I mostly note it here because this transition is probably the one that most affected me personally as my Microsoft Office 2011 was 32 bit and would not run on Catalina. For this reason I stuck with Mojave until I bought an Arm Mac.
Intel to Arm
The last Intel Mac was released in May 2020.
The first Arm Macs were released in November 2020.
It is expected that MacOS 26 is the last version of MacOS to support Intel Macs. MacOS 27 is expected to not support Intel Macs and is likely to be released in October 2026.
Arm Macs include an Intel emulator called Rosetta 2. It is expected that this emulator will be substantially disabled with MacOS 28, which is likely to be released around October 2026.
Summary
| Architecture | How long current was it the current architecture? | How long after last mac released until not supported by new OS? | How long after new architecture macs released was software in this architecture supported supported in OS? |
|---|---|---|---|
| 68K | 10 years, 7 months Jan 1984-August 1995 | 3 years, 2 months August 1995-October 1998 | 7 years March 1994 – March 2001 (release of Mac OSX) / 13 years, 7 months March 1994 – October 2007 (release of Leopard) |
| PPC | 11 years, 8 months March 1994 – November 2005 | 3 years, 8 months November 2005 – August 2009 | 5 years, 6 months January 2006 – July 2011 |
| Intel | 14 years, 4 months January 2006 – May 2020 | 6 years, 5 months May 2020 – October 2026? | 6 years, 11 months November 2020 – October 2027? |
References
List of Mac Models grouped by CPU type – This page lists when all Macs were released and discontinued, and what processor they used.