Retailing for US$3,898 base price (for the CPU unit only), the Macintosh II was the first "modular" Macintosh model, so called because it came in a horizontal desktop case like many PCs of the time. All previous Macintosh computers used an all-in-one design with a built-in black-and-white monitor.
The primary improvement in the Mac II was Color QuickDraw in ROM, a color version of the graphics language which was the heart of the machine. Among the many innovations in Color QuickDraw were an ability to handle any display size, any color depth, and multiple monitors. Because the Color QuickDraw language was in ROM, earlier Macintoshes could not display color, and many early adopters felt betrayed by Apple. After a year or two, Apple changed direction and began shipping Color QuickDraw in the operating system, allowing earlier computers to run color programs with 1-bit color.
The Macintosh II was designed by hardware engineers Michael Dhuey (computer) and Brian Berkeley (monitor). A basic system with 20 Mb drive and monitor cost about $5200, A complete color-capable system could cost as much as $10,000 once the cost of the color monitor, video card, hard disk and RAM were added. This price point placed it in competition with workstations from Silicon Graphics, Sun and Hewlett-Packard.
Introduced in 1987, the Mac II featured a Motorola 68020 processor operating at 16 MHz teamed with a Motorola 68881 floating point unit. The machine shipped with a socket for an MMU, but an Apple chip was installed that did not implement virtual memory (the software for virtual memory would not be released until 1990.) Standard memory was 1 megabyte, expandable to 68 MB, though not without the special FDHD upgrade kit; otherwise, 20 MB was the maximum. RAM could be maxed out to 128 MB, however, if the ROMs were upgraded to those used in the IIx (or if MODE32 was used), as the Mac II's memory controller supported higher-density memory modules than did the stock ROM. The Mac II had eight 30-pin SIMMs, and memory was installed in groups of four. A 5.25-inch 40 MB internal SCSI hard disk was optional, as was a second internal 800 kilobyte 3.5-inch floppy disk drive. Six NuBus slots were available for expansion (at least one of which had to be used for a graphics card, as the Mac II had no onboard graphics).
The Macintosh II was followed by a series of related models including the Macintosh IIx and Macintosh IIfx, all of which used the Motorola 68030 processor. It was possible to upgrade a Macintosh II to a Macintosh IIx or IIfx with a motherboard swap. The Macintosh II was the first Macintosh to have the Chimes of Death accompany the Sad Mac logo whenever a serious hardware error occurred.