The Macintosh SE/30 is a personal computer designed, manufactured and sold by Apple Computer from January 1989 to October 1991. It is the fastest of the original black-and-white compact Macintosh series.

The SE/30 has a black-and-white monitor and a single Processor Direct Slot (rather than the NuBus slots of the IIx, with which the SE/30 shares a common architecture) which supported third-party accelerators, network cards, or a display adapter. The SE/30 could expand up to 128 MB of RAM (a significant amount of RAM at the time), and included a 40 or 80 MB hard drive. It was also the first compact Mac to include a 1.44 MB high density floppy disk drive as standard (late versions of the SE had one, but earlier versions did not). The power of the SE/30 was demonstrated by its use to produce the This Week newspaper, the first colour tabloid newspaper in the UK to use new, digital pre-press technology on a personal, desktop computer. In keeping with Apple's practice, from the Apple II+ until the Power Macintosh G3 was announced, a logic board upgrade was available for US$1,699 to convert a regular SE to an SE/30. The SE would then have exactly the same specs as an SE/30, with the difference only in the floppy drive if the SE had an 800 KB drive. The set included a new front bezel to replace the original SE bezel with that of an SE/30.

Although this machine was succeeded in Q4 of 1990 by the Macintosh Classic, the SE/30 wasn't discontinued until 1991 by the Macintosh Classic II, which despite featuring the same processor and clock speed, was only 60% as fast as the SE/30 due to its 16-bit data path, supported no more than 10 MB of memory, lacked an internal expansion slot, and made the Motorola 68882 FPU an optional upgrade.

Hardware

Although the Motorola 68030 in the SE/30 supports 32-bit addressing, the SE/30 ROM, like the IIx ROM, includes some code using 24-bit addressing, rendering the ROM "32-bit dirty". This limits the actual amount of RAM that can be accessed to 8 MB under System 6.0.8. A system extension called MODE32 enables access to installed extra memory under System 6.0.8. Under System 7.0 up to System 7.5.5 the SE/30 can use up to 128 MB of RAM.  Alternatively, replacing the ROM SIMM with one from a Mac IIsi or Mac IIfx makes the SE/30 "32-bit clean" and thereby enables use of up to 128 MB RAM and System 7.5 through OS 7.6.1.

A standard SE/30 can run up to System 7.5.5, since Mac OS 7.6 requires a "32-bit clean" ROM.

Additionally, the SE/30 can run A/UX, Apple's older version of Unix that was able to run Macintosh programs.

Though there was no official upgrade path for the SE/30, several third-party processor upgrades were available. A 68040 upgrade made it possible to run Mac OS 8.1, which extended the SE/30's productive life for many more years. 
Also extending the useful life of the SE30 were Micron Technology video cards.  Three cards were available, which fit into the SE/30's Processor Direct Slot: the 8-bit Gray-Scale 30, the SE/306-48, 640x480 resolution 8-bit color, and SE/3010-78 1024x768 resolution 8-bit color.  With the first, the internal display was 8-bit greyscale; the latter two were used with 13" and 14", respectively, external color monitors, while retaining 1-bit (black and white) on the internal monitor.

Models
 Macintosh SE/30: Available in multiple configurations.
 : 1 MB RAM, No hard disk
 : 1 MB RAM, 40 MB hard disk
 : 4 MB RAM, 80 MB hard disk

Reception
Bruce F. Webster wrote in Macworld in March 1989 that the SE/30 did not "break new ground. It does, however, establish Apple's commitment to the classic Mac product line, and it provides users with an Apple-supported alternative to either a small, slow Mac or a large, powerful one. More important, it fills a gap in the Macintosh family ... a new level of power and portability for the Macintosh community". 

In a January 2009 Macworld feature commemorating the 25th anniversary of the Macintosh, three industry commentators – Adam C. Engst of TidBITS, John Gruber of Daring Fireball, and John Siracusa of Ars Technica – chose the SE/30 as their favorite Mac model of all time. "Like any great Mac," wrote Gruber, "the SE/30 wasn't just a terrific system just when it debuted; it remained eminently usable for years to come. When I think of the original Mac era, the machine in my mind is the SE/30."

The SE/30 remains popular with hobbyists, and has been described as “the best computer Apple will ever make,” with used models selling for a significant premium relative to other machines of the era. Contemporary PDS upgrades allowed an SE/30's internal monitor to be upgraded to support 256 shades of gray (the only original-design Macintosh to support such an upgrade) or a 68040 processor, and the SE/30's standard RAM limit of 128 MB greatly exceeded even that of much later models such as the Color Classic and Macintosh LC II.  In 2018, add-ons and software became available to add WiFi and even make the SE/30 work as a remote control for Spotify.

In popular culture
In the NBC TV series Seinfeld, Jerry has an SE/30 sitting on his desk during the first seasons. This would be the first of many Macs to occupy the desk, including a PowerBook Duo and a Twentieth Anniversary Macintosh.

In the FX series It's Always Sunny in Philadelphia, the Waitress is seen with a Macintosh SE/30 on her bedroom desk in the episode "The Gang Gives Back".

In the film Watchmen, Ozymandias has an all-black TEMPEST-shielded SE/30 on his desk.

Timeline

References

SE 30
SE 30
SE 30
Computer-related introductions in 1989

sv:Macintosh SE#SE/30