From Surf Wiki (app.surf) — the open knowledge base

Macintosh IIsi

Personal computer by Apple, Inc

Field	Value
name	Macintosh IIsi
family	Macintosh II
developer	Apple Computer, Inc.
image	Macintosh IIsi 2.jpg
caption	A Macintosh IIsi
release_date
price
cpu	Motorola 68030
cpu_speed	20 MHz
os	System 6.0.7 – Mac OS 7.6.1, with 68040 upgrade Mac OS 8.1
memory	1 MB, expandable to 17 MB
memory_type	100 ns 30-pin SIMMs
dimensions	Height: 4 in
Width: 12.4 in
Depth: 14.9 in
weight	10 lb
discontinued
successor	Macintosh Centris 610

Width: 12.4 in Depth: 14.9 in

The Macintosh IIsi is a personal computer designed, manufactured and sold by Apple Computer, Inc. from October 1990 to March 1993. Introduced as a lower-cost alternative to the other Macintosh II family of desktop models, it was popular for home use, as it offered more expandability and performance than the Macintosh LC, which was introduced at the same time. Like the LC, it has built-in sound support, as well as support for color displays, with a maximum screen resolution of 640 × 480 in 8-bit color.{{cite web | access-date = September 18, 2022 | archive-date = November 5, 2013 | archive-url = https://web.archive.org/web/20131105073432/http://support.apple.com/kb/SP199 | url-status = live

The IIsi remained on the market for two and a half years and was discontinued shortly after the introduction of its replacement, the Centris 610.

Hardware

The IIsi's case design is a compact desktop unit not used for any other Macintosh model, one of the few Macintosh designs that was used for a single model. Positioned below the Macintosh IIci as Apple's entry-level professional model, the IIsi's price was lowered by the redesign of the motherboard substituting a different memory controller and the deletion of all but one of the expansion card slots (a single Processor Direct Slot) and removal of the level 2 cache slot.

It shipped with either a 40 MB or 80 MB internal hard disk, and a 1.44 MB floppy disk drive. The Motorola 68882 FPU was an optional upgrade, mounted on a special plug-in card. Ports included SCSI, two serial ports, an ADB port, a floppy drive port, and 3.5mm stereo headphone sound output and microphone sound input sockets.

A bridge card was available for the IIsi to convert the Processor Direct slot to a standard internal NuBus card slot, compatible with other machines in the Macintosh II family. The bridge card included the 68882 FPU to improve floating-point performance. The NuBus card was mounted horizontally above the motherboard.

To cut costs, the IIsi's video shared the main system memory, which also slowed down video considerably, especially as the IIsi had 1 MB of slow RAM soldered to the motherboard. David Pogue's book Macworld Macintosh Secrets observed that one could speed up video considerably if one set the disk cache size large enough to force the computer to draw video RAM from the faster RAM installed in the SIMM banks.

The IIsi also suffers from sound difficulties: over time, the speaker contacts can fail, causing the sound to periodically drop out. This problem was caused by the very modular construction of the computer, where the mono loudspeaker is on a daughterboard under the motherboard, with springy contacts. Speaker vibrations led to fretting of the touching surfaces. The problem could be solved by removing the motherboard and using a pencil eraser to clean the contacts of the daughterboard holding the loudspeaker. As the IIsi is the only Macintosh to use this case design, these issues were never corrected in a subsequent model. The IIsi was designed to be easily and cheaply manufactured, such that no tools were required to put one together – everything is held in place with clips or latches.

Because of its heritage as a cut-down IIci, it was a simple modification to substitute a new clock crystal to increase the system's clock rate to 25 MHz for a slight increase in performance and a large increase in video rendering speed.

Known users

Charles Bukowski was an enthusiastic user of the IIsi.

Timeline

References

(May 8, 2010). "Macintosh IIsi Teardown".
"Reality Studio essay on Charles Bukowski's computer use".

Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

macintosh-ii 68k-macintosh-computers macintosh-desktops a/ux-capable-macintoshes macintosh-case-designs computer-related-introductions-in-1990 products-and-services-discontinued-in-1993

Want to explore this topic further?

Ask Mako anything about Macintosh IIsi — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report