Editing Macintosh Performa 550

{{Infobox computer
| name         = Macintosh Performa 550
| image        = [[File:Macintosh_LC_575.jpg]]
| caption      = Macintosh Performa 550
| manufacturer = Apple Computer, Inc.
| type         = All-in-One Personal Computer
| release_date = October 18, 1993
| discontinued = April 1, 1996
| price        = US$2,000
| cpu          = Motorola 68030 @ 33 MHz
| memory       = 5 MB RAM (expandable to 36 MB)
| storage      = 160 MB SCSI hard drive, 2X CD-ROM, 1.44 MB floppy
| display      = 14" Sony Trinitron color CRT (640×480)
| sound        = Stereo 8-bit, 22 kHz
| dimensions   = 17.9" H × 13.5" W × 16.5" D (45.5 × 34.3 × 41.9 cm)
| weight       = 40.5 lbs (18.4 kg)
| os           = System 7.1P – System 7.6.1
| predecessor  = [[Macintosh Performa 520|Performa 520]]
| successor    = [[Macintosh Performa 575|Performa 575]]
| codename     = Hook
| model        = M1640
}}

The '''Macintosh Performa 550''' is an all-in-one personal computer introduced by Apple Computer on October 18, 1993.<ref>{{cite web |url=https://everymac.com/systems/apple/mac_performa/specs/mac_performa_550.html |title=Macintosh Performa 550 Specs |publisher=EveryMac.com |access-date=2026-02-10}}</ref> It is the consumer version of the [[Macintosh LC 550|LC 550]], sold through retail channels with bundled "home software."

The Performa 550 shares identical hardware with the [[Macintosh LC 550|LC 550]], differing only in the included software bundle and distribution channel. The LC 550 was sold to educational institutions while the Performa 550 targeted home users.

== Relationship to LC 550 ==

The Performa 550 uses the same logic board, case design, and internal components as the [[Macintosh LC 550|LC 550]]. Apple marketed the same hardware under different names for different markets:

* '''[[Macintosh LC 550|LC 550]]''' – Educational market
* '''Performa 550''' – Consumer market (home software bundle)
* '''[[Macintosh Performa 560|Performa 560]]''' – Consumer market (business software bundle)

== Architecture and Processor ==

The Performa 550 uses a Motorola 68030 processor running at 33 MHz with a 32-bit data bus. The system bus also operates at 33 MHz. An optional Motorola 68882 FPU can be installed for floating-point calculations.

== Memory and Storage ==

=== RAM Configuration ===

The system includes 4 MB of RAM soldered to the logic board, with an additional 1 MB SIMM installed by default for a total of 5 MB. A single 72-pin SIMM slot accepts modules up to 32 MB for a maximum of 36 MB total RAM. SIMMs must be 80 ns or faster.

=== ROM ===

The Performa 550 contains 1 MB of ROM.

=== Storage Systems ===

Standard configuration includes a 160 MB internal SCSI hard drive, a 2X CD-ROM drive, and a 1.44 MB SuperDrive floppy.

== Display and Graphics ==

The built-in 14-inch Sony Trinitron CRT displays 640×480 resolution in 16-bit color. The system includes 512 KB of VRAM soldered to the logic board. A single VRAM slot accepts a 256 KB VRAM SIMM, bringing the total to 768 KB for improved color depth.

A second display can be supported via an LC PDS video card.

== Input/Output and Expansion ==

=== Port Configuration ===

* 2× Serial ports (Printer, Modem)
* SCSI port (DB-25)
* ADB port
* Audio input/output jacks

=== Expansion ===

The Performa 550 includes one LC PDS slot for expansion cards such as Ethernet adapters or additional video output.

== General Maintenance ==

For detailed maintenance practices including cleaning, PRAM battery management, connector corrosion prevention, and voltage adjustments, refer to the dedicated [[Macintosh LC 550 General Maintenance]] page.

== PCB Schematics & Service Manual ==

The Macintosh Performa 550 shares its logic board and analog board with the [[Macintosh LC 550|LC 550]]. For schematics and service documentation, see the [[Macintosh LC 550]] article.

All Apple Service Manuals can be found on the [[:Category:Apple Service Source|Apple Service Source]] page.

== Capacitor Replacement Guide ==

Detailed capacitor replacement guidelines for both analog and logic boards can be found on the [[Macintosh LC 550 Capacitor Replacement Guide]] page.

== Retrobrite ==

To address plastic yellowing, detailed instructions can be found on the [[Retrobrite]] page.

== Troubleshooting ==

A comprehensive troubleshooting guide addressing no power, chime but no video, intermittent operation, Sad Mac errors, and floppy drive problems is available on the [[Macintosh LC 550 Troubleshooting]] page.

== Technical Details ==

<templatestyles src="Template:StyledTable/styles.css" />

=== System Architecture at a Glance ===

{| class="wikitable styled-table" style="width:90%; text-align:center;"
! Sub-system !! Specification
|-
| '''CPU''' || Motorola 68030 @ 33 MHz
|-
| '''FPU''' || Optional Motorola 68882
|-
| '''Bus width''' || 32-bit data bus
|-
| '''ROM''' || 1 MB
|-
| '''RAM''' || 5 MB standard (4 MB soldered + 1 MB SIMM), expandable to 36 MB
|-
| '''VRAM''' || 512 KB (expandable to 768 KB)
|-
| '''Video''' || 640×480, 16-bit color
|-
| '''Sound''' || Stereo 8-bit, 22 kHz
|-
| '''Storage''' || 160 MB SCSI HDD, 2X CD-ROM, 1.44 MB floppy
|-
| '''Expansion''' || 1× LC PDS slot
|-
| '''Gestalt ID''' || 80
|}

== References ==

<references />

== Service Documentation ==

The official Apple Service Source documentation for this model:

<pdf width="800" height="500">File:Lc_520.550.575.pdf</pdf>

== See Also ==

* [[Macintosh LC 550]]
* [[Macintosh Performa 560]]
* [[Macintosh Performa 520]]
* [[Macintosh Performa 575]]

[[Category:Apple Vintage Computers]]