Described by MacWorld Magazine as "The most important technical evolution of the Macintosh since the Mac II debuted in 1987," the Power Macintosh was Apple's first computer to use a PowerPC processor. Software written for the Motorola 68030 and 68040 processors that were used in Macintoshes up to that point would not run on the PowerPC natively, so a Mac 68k emulator was included with System 7.1.2. While the emulator provided good compatibility with existing Macintosh software, performance was about one-third slower than comparable Macintosh Quadra machines.