Processor and Software
The ROM and Mac OS operating system released with the new Power Mac machines included an Mac 68K emulator to enable programs written for Motorola 68k series CPUs, including nearly all prior Mac software, to run without changes. (A similar scheme is employed to run 68K software on modern x86 Alpha Microsystems machines.) As the Power Mac was originally intended to be a part of the high end of Apple's product line, for a number of years the company continued to offer less expensive 68k-based computers alongside the more expensive Power Mac lineup. However, for many of these so-called 68K transition Macs, Apple offered an upgrade path in the form of a PowerPC Macintosh Processor Upgrade Card and aggressively marketed it to assure a wary consumer of their investment. In April 1996, Apple discontinued the Macintosh LC 580 (released in 1995), the last remaining desktop model of the 68k-based Macintosh line. The PowerBook 190cs, the last 68k-based PowerBook, was discontinued in October 1996. All subsequent Macintosh computers would be based on PowerPC processors until 2006, when Apple switched to Intel processors.
Read more about this topic: Power Macintosh