Editing Macintosh Centris 610

{{Infobox computer
| name         = Macintosh Centris 610
| image        = [[File:Macintosh_Quadra_610.jpg]]
| caption      = Macintosh Centris 610 (identical case to Quadra 610)
| manufacturer = Apple Computer, Inc.
| type         = Personal Computer
| release_date = February 10, 1993
| discontinued = October 21, 1993
| price        = US$1,860–$2,520
| cpu          = Motorola 68LC040 @ 20 MHz
| memory       = 4 MB RAM soldered (expandable to 68 MB)
| storage      = 80–500 MB SCSI hard drive, 1.44 MB floppy
| display      = Supports up to 1152×870 (8-bit with 1 MB VRAM)
| sound        = 8-bit stereo
| dimensions   = 3.4" H × 16.3" W × 15.6" D (8.6 × 41.4 × 39.6 cm)
| weight       = 14 lbs (6.4 kg)
| os           = System 7.1 – Mac OS 8.1
| predecessor  = [[Macintosh IIsi]]
| successor    = [[Macintosh Quadra 610]]
| codename     = Speedbump 610
| model        = M1444
}}

The '''Macintosh Centris 610''' is a personal computer designed and manufactured by Apple Computer, released on February 10, 1993.<ref>{{cite web |url=https://everymac.com/systems/apple/mac_centris/specs/mac_centris_610.html |title=Macintosh Centris 610 Specs |publisher=EveryMac.com |access-date=2026-02-10}}</ref> It was introduced as the entry-level model in Apple's new Centris line, positioned between the consumer Macintosh LC series and the professional Quadra series.<ref>{{cite web |url=https://lowendmac.com/1993/centris-610/ |title=Centris 610 |publisher=Low End Mac |access-date=2026-02-10}}</ref>

The Centris 610 introduced a new low-profile "pizza box" case design that would later be used for the [[Macintosh Quadra 660AV]] and [[Power Macintosh 6100]]. In October 1993, the Centris 610 was renamed to [[Macintosh Quadra 610]] with a processor speed bump to 25 MHz as Apple consolidated its product naming strategy.<ref>{{cite web |url=https://en.wikipedia.org/wiki/Macintosh_Quadra_610 |title=Macintosh Quadra 610 |publisher=Wikipedia |access-date=2026-02-10}}</ref>

== Model Variants ==

The Centris 610 was sold in four configurations at launch:<ref>{{cite web |url=https://support.apple.com/en-us/112212 |title=Macintosh Centris 610: Technical Specifications |publisher=Apple Inc. |access-date=2026-02-10}}</ref>

* '''Base model''' (M1345LL/A): 4 MB RAM, 80 MB HDD, no Ethernet — US$1,860
* '''Mid-range''': 8 MB RAM, 80 MB HDD, Ethernet
* '''Upper mid-range''' (M1397LL/A): 8 MB RAM, 230 MB HDD, Ethernet — US$2,560
* '''High-end''' (M1398LL/A): 8 MB RAM, 1 MB VRAM, 230 MB HDD, 2× CD-ROM, Ethernet, microphone

A server variant, the '''Workgroup Server 60''', was introduced in July 1993 with a full 68040 processor.

== Architecture and Processor ==

The Centris 610 uses a Motorola 68LC040 processor running at 20 MHz. The "LC" designation indicates the processor lacks an integrated floating-point unit (FPU). The 68LC040 can be replaced with a full 68040 to add FPU capability.<ref>{{cite web |url=https://lowendmac.com/1993/centris-610/ |title=Centris 610 |publisher=Low End Mac |access-date=2026-02-10}}</ref>

* '''CPU:''' Motorola 68LC040 @ 20 MHz
* '''Data bus:''' 32-bit
* '''Address bus:''' 32-bit
* '''L1 cache:''' 8 KB (integrated)
* '''ROM:''' 1 MB

=== Memory ===

* '''Onboard RAM:''' 4 MB soldered to logic board
* '''RAM slots:''' 2 × 72-pin SIMM
* '''Maximum RAM:''' 68 MB<ref name="ss610">Apple Computer, ''Macintosh Quadra 610/Centris 610/WS 60 Service Source'' ([[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], [[:File:Quadra.centris_610.ws_60.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>
* '''RAM speed:''' 80 ns or faster
* '''Supported SIMMs:''' 4, 8, 16, or 32 MB

If SIMMs of different speeds are used, the faster SIMM should be installed in bank 0 (frontmost slot).

=== Storage ===

* '''Floppy drive:''' 1.44 MB SuperDrive (auto-inject)
* '''Hard drive:''' 80, 230, or 500 MB internal SCSI
* '''CD-ROM:''' Optional 2× AppleCD 300i (internal)
* '''SCSI interface:''' external DB-25. Apple: '''a maximum of six external devices''', the computer itself always being device 7<ref name="ss610">Apple Computer, ''Macintosh Quadra 610/Centris 610/WS 60 Service Source'' ([[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], [[:File:Quadra.centris_610.ws_60.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>

== Display and Graphics ==

The Centris 610 includes built-in video output via a DB-15 connector. VGA monitors can be connected using an adapter.

* '''VRAM:''' 512 KB onboard, expandable to 1 MB via SIMM
* '''VRAM slots:''' 2 (accepts 256 KB or 512 KB VRAMs)

{| class="wikitable" style="width:70%"
|+ '''Display Resolutions'''
|-
! Resolution !! 512 KB VRAM !! 1 MB VRAM
|-
| 512 × 384 || 16-bit || 16-bit
|-
| 640 × 480 || 8-bit || 16-bit
|-
| 800 × 600 || 8-bit || 16-bit
|-
| 832 × 624 || 8-bit || 16-bit
|-
| 1024 × 768 || 4-bit || 8-bit
|-
| 1152 × 870 || 4-bit || 8-bit
|}

== Input/Output and Expansion ==

=== Port Configuration ===

* '''ADB ports:''' 2 (keyboard, mouse)
* '''Serial ports:''' 2 (DIN-8 printer and modem)
* '''SCSI:''' 1 (DB-25 external)
* '''Video:''' 1 (DB-15)
* '''Audio:''' Speaker out, microphone in
* '''Ethernet:''' AAUI-15 (optional on some configurations)

=== Expansion Slots ===

The Centris 610 has a single Processor Direct Slot (PDS). A NuBus adapter (Apple part M1402LL/A) allows installation of one 7-inch NuBus card. Only 7-inch NuBus cards fit; standard 12-inch cards will not work.<ref>{{cite web |url=https://en.wikipedia.org/wiki/Macintosh_Quadra_610 |title=Macintosh Quadra 610 |publisher=Wikipedia |access-date=2026-02-10}}</ref>

The low clearance of the case initially prevented use of the full 68040 processor, which requires a heatsink that the 68LC040 does not need.

== Power ==

* '''Line voltage:''' 100–240 VAC
* '''Line frequency:''' '''50–60 Hz''' — Apple's figure for this machine
* '''Maximum power:''' '''112 W''', not including the monitor<ref name="ss610">Apple Computer, ''Macintosh Quadra 610/Centris 610/WS 60 Service Source'' ([[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], [[:File:Quadra.centris_610.ws_60.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>
* '''PRAM battery:''' 3.6 V ½AA lithium. Apple's instruction is to '''replace it below 3.2 V'''<ref name="ss610">Apple Computer, ''Macintosh Quadra 610/Centris 610/WS 60 Service Source'' ([[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], [[:File:Quadra.centris_610.ws_60.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>

'''86 W circulates for this machine as the maximum power. That is the Centris 660AV's figure''', not this machine's; Apple gives 112 W for the 610.

The power switch is located on the front panel. Unlike the Mac II series, the Centris 610 cannot be powered on or off via the keyboard power key.

== General Maintenance ==
For detailed maintenance practices including cleaning, PRAM battery management, connector corrosion prevention, and voltage adjustments, refer to the dedicated [[Macintosh Centris 610 General Maintenance]] page.

== Capacitor Replacement Guide ==
Detailed capacitor replacement guidelines for the logic board can be found on the [[Macintosh Centris 610 Capacitor Replacement Guide]] page.

== Troubleshooting ==
A comprehensive troubleshooting guide addressing no power, chime but no video, intermittent operation, and other issues is available on the [[Macintosh Centris 610 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 (Macintosh Centris 610, 1993)
|-
| '''CPU''' || Motorola 68LC040 @ 20 MHz
|-
| '''Bus width''' || 32-bit data • 32-bit address
|-
| '''ROM''' || 1 MB
|-
| '''RAM''' || 4 or 8 MB standard, expandable to '''68 MB''' (80 ns or faster 72-pin SIMMs)<ref name="ss610">Apple Computer, ''Macintosh Quadra 610/Centris 610/WS 60 Service Source'' ([[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], [[:File:Quadra.centris_610.ws_60.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>
|-
| '''Video''' || Up to 1152 × 870 (built-in)
|-
| '''Sound''' || 8-bit stereo
|-
| '''Disks''' || 1.44 MB floppy, 80–500 MB SCSI HDD
|-
| '''Ports''' || ADB × 2, Serial × 2, SCSI, Video, Audio
|}

=== Processor Specifications ===
{| class="wikitable styled-table"
|-
! Component !! Specification
|-
| CPU || Motorola 68LC040 @ 20 MHz<ref>{{cite web |url=https://support.apple.com/en-us/112212 |title=Macintosh Centris 610: Technical Specifications |publisher=Apple Inc. |access-date=2026-02-10}}</ref>
|-
| FPU || None (68LC040 variant)
|-
| Data Bus || 32-bit
|-
| Address Bus || 32-bit
|-
| Gestalt ID || 52
|-
| Model Number || M1444
|}

== Service documentation ==

Apple's own service manual is hosted here as
[[Macintosh Quadra 610/ Centris 610/WS 60 Service Source]], which covers the Centris 610 alongside
the Quadra 610, the Quadra 610 DOS Compatible and the Workgroup Server 60. It gives the supply as
'''100–240 VAC''' at 50–60 Hz drawing '''112 W''' excluding the monitor, and the PRAM cell threshold
as '''replace below 3.2 V'''.<ref name="ssmacintoshcentris">Apple Computer, ''Macintosh Centris 610'', Service Source, 103 pp, PDF distilled 20 November 1995. Hosted here as the wiki page linked above ([[:File:quadra.centris_610.ws_60.pdf]]). Specifications chapter, and Additional Procedures — Battery Verification where a threshold is quoted.</ref>

Its Troubleshooting chapter stops at Peripheral — there is '''no Miscellaneous and no Error Chords
section''' — so an unexplained startup chord on one of these has to be worked out elsewhere.<ref name="ssmacintoshcentris" />

<pdf width="800" height="500">File:Quadra.centris_610.ws_60.pdf</pdf>

== See Also ==

* [[Macintosh Quadra 610]] — The renamed/upgraded successor
* [[Macintosh Centris 650]] — Mid-range Centris model
* [[Macintosh IIsi]] — Predecessor
* [[Power Macintosh 6100]] — Uses the same case design

== References ==
<references />

[[Category:Apple Vintage Computers]]