Apple Macintosh 512K

The Macintosh 512K, released in September 1984 as the second model in Apple’s Macintosh line, expanded on the original 128K by increasing memory to 512KB, enabling more capable software and smoother performance. It retained the 7.8MHz Motorola 68000 processor and the familiar 512 × 342 monochrome display, along with the single-sided 400KB floppy drive used by early compact Macs. Like the 128K, the 512K lacked a SCSI port, relying instead on floppy-based storage and, later, the optional HD20 hard disk connected through the floppy port. Its keyboard used an RJ-11 connector, while the mouse attached via a DE-9, predating the ADB standard introduced with the Macintosh SE.