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House rule: reword in-article correction narratives so they describe the claim in circulation and what the source says, rather than the page's own edit history. The corrections themselves are recorded in the edit summaries
Correct power (230 W was Apple's figure for the Power Mac upgrade-card configuration; base machine 112 W per Service Source and dev note) and RAM (136 MB is right with 8 MB on board); tantalum claim now cited (Retro Viator); Centris 650 photo replaces Quadra 650 photo; configs table; parts; cite dev note
 
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{{Infobox computer
{{Infobox computer
| name        = Macintosh Centris 650
| name        = Macintosh Centris 650
| image        = [[File:Quadra_650_Front.jpg]]
| image        = [[File:Macintosh Centris 650 (photo).jpg|260px|frameless]]
| caption      = Macintosh Centris 650
| caption      = Centris 650 at the Apple Museum, Prague (photo: Benoît Prieur, CC0)
| manufacturer = Apple Computer, Inc.
| manufacturer = Apple Computer, Inc.
| type        = Personal Computer
| type        = Desktop personal computer
| release date = February 10, 1993
| release_date = 10 February 1993
| discontinued = October 21, 1993 (renamed to Quadra 650)
| discontinued = 21 October 1993
| price        = US$2,699–$3,800
| price        = US$2,700, $3,400 and $3,800 (three configurations)
| cpu          = Motorola 68040 @ 25 MHz (or 68LC040)
| cpu          = Motorola MC68040 @ 25 MHz (MC68LC040 in the entry model)
| memory      = 4 or 8 MB RAM, expandable to 132 MB
| memory      = 4 or 8 MB on the logic board; four 72-pin SIMM slots; 132 or 136 MB maximum
| storage      = 80–500 MB SCSI HDD, optional 2X CD-ROM
| rom          = 1 MB
| display      = Up to 1152×870 (with VRAM expansion)
| storage      = 1.4 MB SuperDrive; 80–500 MB SCSI hard drive; optional internal CD-ROM
| sound        = 8-bit stereo sound
| display      = External monitor via DB-15; 512 KB VRAM, 1 MB maximum
| dimensions  = 6" H × 13" W × 16.5" D (15.2 × 33 × 41.9 cm)
| sound        = 8-bit stereo output, mono input
| weight      = 25 lbs (11.3 kg)
| expansion    = Three NuBus slots and one processor-direct slot
| power        = 100–240 V AC, 112 W maximum
| dimensions  = 152 × 330 × 419 mm (6.0 × 13.0 × 16.5 in) H × W × D
| weight      = 11.3 kg (25 lb), varying with the drives fitted
| os          = System 7.1 – Mac OS 8.1
| os          = System 7.1 – Mac OS 8.1
| predecessor  = [[Macintosh IIci]]
| successor    = [[Macintosh Quadra 650]]
| successor    = Power Macintosh 7100
| codename    =
| model        = M1205
| model        = M1205
}}
}}
The '''Macintosh Centris 650''' is a personal computer designed, manufactured, and sold by Apple Computer from February 1993 to October 1993.<ref>{{cite web |url=https://support.apple.com/kb/SP230 |title=Centris 650: Technical Specifications |publisher=Apple |access-date=2026-02-10}}</ref> It was introduced alongside the smaller [[Macintosh Centris 610]] as a replacement for the [[Macintosh IIci]] and [[Macintosh Quadra 700]].<ref>{{cite web |url=https://everymac.com/systems/apple/mac_centris/specs/mac_centris_650.html |title=Macintosh Centris 650 Specs |publisher=EveryMac.com |access-date=2026-02-10}}</ref>
The '''Macintosh Centris 650''' is a desktop Macintosh with a 25 MHz Motorola 68040, three NuBus slots and a processor-direct slot. Apple introduced it on 10 February 1993, with the [[Macintosh Centris 610]], and discontinued it on 21 October 1993.<ref name="em">{{cite web |url=https://everymac.com/systems/apple/mac_centris/specs/mac_centris_650.html |title=Apple Macintosh Centris 650 Specs |publisher=EveryMac.com |access-date=2026-09-30}} Dates, configurations and order numbers, prices, model M1205, Gestalt ID 30, supported Mac OS 7.1–8.1, 3.6 V lithium battery.</ref> It was replaced by the [[Macintosh Quadra 650]], the same machine with a 33 MHz 68040; Apple services the two from one ''Service Source'' volume.<ref name="ss650spec">Apple Computer, ''Centris 650/Quadra 650 Service Source'', Specifications, pp. 1-11 (PDF pp. 5-15). Hosted as [[:File:Quadra.centris_650.pdf]]; see [[Centris 650/Quadra 650 Service Source]].</ref> The case is the desktop design of the [[Macintosh IIvx]] and Performa 600.<ref name="dn3">Apple Computer, ''Developer Note: Macintosh Centris 610, Macintosh Centris 650, and Macintosh Quadra 800 Computers'' (1993), "Product Designs", p. 3 (PDF p. 15). Hosted as [[:File:Macintosh Centris 610 Centris 650 and Quadra 800 Developer Note.pdf]]; see [[Macintosh Centris 610 Centris 650 and Quadra 800 Developer Note]].</ref>


In October 1993, Apple renamed the Centris 650 to the '''[[Macintosh Quadra 650]]''' and increased the processor speed to 33 MHz. The Centris and Quadra 650 share the same logic board and case design, which was originally introduced with the [[Macintosh IIvx]].<ref>{{cite web |url=https://en.wikipedia.org/wiki/Macintosh_Quadra_650 |title=Macintosh Quadra 650 |publisher=Wikipedia |access-date=2026-02-10}}</ref>
== Configurations ==
 
== Model Variants ==
 
The Centris 650 was sold in several configurations:
 
* '''Entry-level (M1207LL/A):''' 68LC040 @ 25 MHz (no FPU), 4 MB RAM, 512 KB VRAM, 80 MB HDD
* '''Mid-range (M1337LL/A):''' 68040 @ 25 MHz, 8 MB RAM, 512 KB VRAM, 230 MB HDD, Ethernet
* '''CD-ROM Bundle (M1279LL/A):''' 68040 @ 25 MHz, 8 MB RAM, 1 MB VRAM, 230 MB HDD, 2X CD-ROM, Ethernet
 
The later '''Quadra 650''' upgraded the processor to 33 MHz.
 
== Architecture and Processor ==
 
The Centris 650 uses the Motorola 68040 processor running at 25 MHz (33 MHz in the Quadra 650). The entry-level model shipped with a 68LC040, which lacks the integrated floating-point unit (FPU). Third-party processor upgrades were available.<ref>{{cite web |url=https://everymac.com/systems/apple/mac_centris/specs/mac_centris_650.html |title=Macintosh Centris 650 Specs |publisher=EveryMac.com |access-date=2026-02-10}}</ref>
 
=== Processor Specifications ===
<templatestyles src="Template:StyledTable/styles.css" />
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:70%; text-align:center;"
{| class="wikitable styled-table" style="width:90%;"
|+'''Centris 650 configurations (EveryMac)'''<ref name="em" />
! Order number !! Processor !! RAM !! VRAM !! Hard drive !! Other
|-
|-
! Component !! Specification
| M1207LL/A || 68LC040 (no FPU) || 4 MB || 512 KB || 80 MB ||
|-
|-
| CPU || Motorola 68040 or 68LC040 @ 25 MHz (33 MHz Quadra)
| M1337LL/A || 68040 || 8 MB || 512 KB || 230 MB || Ethernet
|-
|-
| Data Bus || 32-bit
| M1279LL/A || 68040 || 8 MB || 1 MB || 230 MB || Ethernet, 2× CD-ROM
|-
| Address Bus || 32-bit
|-
| L1 Cache || 8 KB
|-
| FPU || Integrated (68040 only)
|-
| System Bus || 25 MHz
|}
|}
EveryMac gives US prices of $2,700, $3,400 and $3,800.<ref name="em" />


== Memory and Storage ==
== Hardware ==
 
=== Processor and memory ===
=== RAM Configuration ===
The 68040 runs at 25 MHz with an integrated MMU and FPU; the entry configuration's 68LC040 has no FPU.<ref name="ss650spec" /><ref name="em" /> The developer note says a 68LC040 can be replaced by a 68040 in its socket.<ref name="dn11">''Developer Note: Centris 610, Centris 650, Quadra 800'', Table 1-1, p. 3 (PDF p. 15).</ref>
 
The Centris 650 has either 4 MB or 8 MB of RAM soldered to the logic board. Four 72-pin SIMM slots accept 80 ns modules in 4 MB, 8 MB, 16 MB, or 32 MB sizes.
 
* '''Minimum RAM:''' 4 MB
* '''Maximum RAM:''' 132 MB (4 MB onboard) or 136 MB (8 MB onboard)
* '''SIMM Type:''' 72-pin, 80 ns or faster
 
RAM can be interleaved for improved performance.
 
=== Video RAM ===


Onboard video supports 512 KB or 1 MB of VRAM via two 80 ns VRAM SIMM slots.
The logic board carries 4 or 8 MB of RAM. Four 72-pin SIMM slots take 80 ns or faster SIMMs of 4, 8, 16 or 32 MB, giving a maximum of 132 MB with 4 MB on the board or 136 MB with 8 MB.<ref name="dnram">''Developer Note: Centris 610, Centris 650, Quadra 800'', "RAM", p. 21 (PDF p. 33).</ref> The ''Service Source'' gives only the 132 MB figure.<ref name="ss650spec" /> ROM is 1 MB and PRAM 256 bytes.<ref name="ss650spec" />


* '''512 KB VRAM:''' 640×480 at 8-bit, 1152×870 at 4-bit
=== Video ===
* '''1 MB VRAM:''' 640×480 at 16-bit, 1152×870 at 8-bit
Built-in video drives one monitor from a DB-15 port, with 512 KB of VRAM expandable to 1 MB. VGA monitors are supported at 640 × 480 and SVGA at 800 × 600, with an adapter cable.<ref name="ss650spec" />


The system cannot be expanded beyond 1 MB VRAM without a NuBus video card.
{| class="wikitable styled-table" style="width:60%; text-align:center;"
 
|+'''Maximum colour depth by resolution'''<ref name="apple">{{cite web |url=https://support.apple.com/en-us/112207 |title=Centris 650: Technical Specifications |publisher=Apple |access-date=2026-09-30}} Apple's page describes the Centris 650 fitted with the Power Macintosh Upgrade Card (PowerPC 601, introduced 14 March 1994); its video, memory and physical figures apply to the base machine.</ref>
=== Storage Systems ===
! Resolution !! 512 KB VRAM !! 1 MB VRAM
 
* '''Internal Hard Drive:''' SCSI, 80 MB, 230 MB, or 500 MB configurations
* '''Floppy Drive:''' 1.44 MB SuperDrive (auto-inject)
* '''CD-ROM:''' Optional internal 2X AppleCD 300i (5.25" bay)
 
== Input/Output and Expansion ==
 
=== Port Configuration ===
 
{| class="wikitable" style="width:70%"
|-
! Port !! Quantity !! Notes
|-
| ADB || 2 || Keyboard and mouse
|-
|-
| Serial (Mini DIN-8) || 2 || Modem and Printer
| 512 × 384 || 16-bit || 16-bit
|-
|-
| External SCSI (DB-25) || 1 || Up to 6 external devices
| 640 × 480 || 8-bit || 16-bit
|-
|-
| AAUI-15 Ethernet || 1 || Some configurations only
| 800 × 600 || 8-bit || 16-bit
|-
|-
| Video (DB-15) || 1 || VGA via adapter
| 832 × 624 || 8-bit || 16-bit
|-
|-
| Sound In || 1 || 3.5mm
| 1024 × 768 || 4-bit || 8-bit
|-
|-
| Sound Out || 1 || 3.5mm
| 1152 × 870 || 4-bit || 8-bit
|}
|}


=== Expansion Slots ===
=== Storage ===
 
An internal 1.4 MB Apple SuperDrive, an 80 to 500 MB SCSI hard drive and an optional internal 5.25-inch CD-ROM drive.<ref name="ss650spec" /> The case holds two internal SCSI devices.<ref name="dn11" /> The external DB-25 SCSI port supports up to six devices; the computer is always SCSI device 7.<ref name="ss650spec" /> The drive at the end of the internal cable must be terminated and other internal devices must not; the logic board terminates the external end automatically when nothing is plugged in.<ref name="dnscsi">''Developer Note: Centris 610, Centris 650, Quadra 800'', "SCSI Bus and Termination", pp. 18-19 (PDF pp. 30-31).</ref>
* '''NuBus Slots:''' 3
* '''Processor Direct Slot (PDS):''' 1 (68040 PDS)
* '''5.25" External Bay:''' 1 (available if CD-ROM not installed)
 
== Power and battery — Apple's figures ==
 
* '''Line voltage:''' 100–240 VAC; '''frequency:''' 50–60 Hz
* '''Maximum power:''' '''112 W''', not including the display
* '''PRAM battery:''' 3.6 V ½AA lithium, '''replace below 3.2 V'''
* '''Dimensions:''' 6.0 in (152 mm) H × 13.0 in (330 mm) W × 16.5 in (419 mm) D; '''weight''' 25 lb
  (11.3 kg), varying with the drives fitted
* '''Environmental:''' operating 10–40 °C, storage −40 to 47 °C, 10–90 % RH non-condensing,
  0–10,000 ft<ref name="ss650">Apple Computer, ''Centris 650/Quadra 650 Service Source'' ([[Centris 650/Quadra 650 Service Source]], [[:File:Quadra.centris_650.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>
 
'''Apple publishes no rail tolerance and no power-supply adjustment for this machine.''' Its
Adjustments chapter does not exist; the volume runs Basics, Specifications, Troubleshooting, Take
Apart, Upgrades and Exploded View.<ref name="ss650">Apple Computer, ''Centris 650/Quadra 650 Service Source'' ([[Centris 650/Quadra 650 Service Source]], [[:File:Quadra.centris_650.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>
 
== General Maintenance ==
 
For detailed maintenance practices including cleaning, PRAM battery management, connector corrosion prevention, and voltage adjustments, refer to the dedicated [[Macintosh Centris 650 General Maintenance]] page.


'''Note:''' The Centris/Quadra 650 logic board uses tantalum capacitors rather than electrolytic capacitors, so the logic board does not require recapping. However, the power supply unit contains electrolytic capacitors that may need replacement.
=== Ports and expansion ===
Two ADB ports (500 mA maximum for all devices), two mini DIN-8 serial ports (RS-232/RS-422), DB-25 SCSI, DB-15 video, stereo sound out, mono sound in, an Ethernet port on configurations that have it, three NuBus slots and one processor-direct slot.<ref name="ss650spec" /><ref name="em" /> Each of the three slots can supply 15 W to a card.<ref name="dn9">''Developer Note: Centris 610, Centris 650, Quadra 800'', "Power Supplies" and Table 1-3, p. 9 (PDF p. 21).</ref>


== PCB Schematics & Service Manual ==
== Power ==
Line voltage is 100–240 V AC at 50–60 Hz, and the maximum power is 112 W, not including the display.<ref name="ss650spec" /> The developer note describes the supply as the same physical size as the Quadra 700's, delivering up to 112 W, with 1.5 A at +5 V and 2.0 A at +12 V left for internal drives after the logic board and cards.<ref name="dn9" /> Apple's online technical specifications page for the Centris 650 gives 230 W, but that page describes the machine fitted with the Power Macintosh Upgrade Card.<ref name="apple" /> The service part number of the supply is 661-0758.<ref name="ss650ev">''Centris 650/Quadra 650 Service Source'', Exploded View (PDF p. 81).</ref>


The Macintosh Centris 650 shares its logic board design with the Quadra 650.
The clock and PRAM run from a 3.6 V lithium battery.<ref name="em" /> Apple's check is to measure it on the 10 V DC range and replace it below 3.2 V.<ref name="ss650batt">''Centris 650/Quadra 650 Service Source'', Additional Procedures, Battery Verification, pp. 1-2 (PDF pp. 60-61).</ref>


=== Apple Service Manual ===
Apple's symptom chart notes that thermal protection circuitry may shut the machine down if the air vents are blocked, and that it should recover after 30 to 40 minutes.<ref name="ss650ts">''Centris 650/Quadra 650 Service Source'', Troubleshooting, Symptom Charts, System, p. 4 (PDF p. 20).</ref>


The Apple Service Source manual covers both the Centris 650 and Quadra 650.
== Capacitors ==
Retro Viator reports that the logic board of a Quadra 650, which Apple services alongside the Centris 650, carried tantalum capacitors and no aluminium electrolytics, while its power supply did contain electrolytics.<ref name="rv">{{cite web |url=https://retroviator.com/2021/09/02/apple-macintosh-quadra-650/ |title=Apple Macintosh Quadra 650 |publisher=Retro Viator |date=2021-09-02 |access-date=2026-09-30}}</ref> Check your own board before ordering parts. See [[Macintosh Centris 650 Capacitor Replacement Guide]].


All Apple Service Manuals can be found on the [[:Category:Apple Service Source|Apple Service Source]] page.
== Upgrades ==
A Power Macintosh card in the processor-direct slot converts the machine to PowerPC, and Apple offered a logic board upgrade to the Power Macintosh 7100/66 or 7100/66AV.<ref name="ss650up">''Centris 650/Quadra 650 Service Source'', Upgrades, Power Macintosh Card and Power Macintosh Upgrade, pp. 9-12 (PDF pp. 76-79).</ref>


== Capacitor Replacement Guide ==
== Service parts ==
 
{| class="wikitable styled-table" style="width:70%;"
Detailed capacitor replacement guidelines can be found on the [[Macintosh Centris 650 Capacitor Replacement Guide]] page.
|+'''Centris 650 / Quadra 650 service parts (Apple exploded view)'''<ref name="ss650ev" />
 
! Part !! Apple part number
'''Important:''' The logic board uses tantalum capacitors and does not require recapping. Only the power supply contains electrolytic capacitors.
 
== Retrobrite ==
 
To address plastic yellowing on the case, detailed instructions can be found on the [[Retrobrite]] page.
 
== Troubleshooting ==
 
A comprehensive troubleshooting guide addressing no power, video issues, and common problems is available on the [[Macintosh Centris 650 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 68040/68LC040 @ 25 MHz (33 MHz Quadra)
|-
| '''Bus width''' || 32-bit data • 32-bit address
|-
| '''ROM''' || 1 MB
|-
| '''RAM''' || 4–8 MB onboard (expandable to '''132 MB''' (Apple's figure; 136 MB is the Quadra 610/660AV-class number and circulates for this machine)<ref name="ss650">Apple Computer, ''Centris 650/Quadra 650 Service Source'' ([[Centris 650/Quadra 650 Service Source]], [[:File:Quadra.centris_650.pdf]]), Specifications chapter and Additional Procedures → Battery Verification.</ref>)
|-
|-
| '''Video''' || Up to 1152×870 with 1 MB VRAM
| Power supply || 661-0758
|-
|-
| '''Sound''' || 8-bit stereo, 22 kHz
| Floppy drive || 661-0121, 661-0474
|-
|-
| '''Disks''' || SCSI HDD, 1.44 MB floppy, optional CD-ROM
| Hard drive / CD-ROM SCSI cable || 922-0053
|-
|-
| '''Expansion''' || 3 NuBus, 1 PDS
| Top cover || 922-0405
|-
|-
| '''Power''' || 100–240V AC, 230W max
| Front panel || 922-0542
|-
|-
| '''Gestalt ID''' || 30
| Speaker || 922-0055
|}
|}
The exploded view gives no logic board part number; it refers to a separate parts list.<ref name="ss650ev" />


== Related Models ==
== Maintenance and repair ==
* [[Macintosh Centris 650 General Maintenance]]
* [[Macintosh Centris 650 Capacitor Replacement Guide]]
* [[Macintosh Centris 650 Troubleshooting]]


* '''[[Macintosh Quadra 650]]''' – Renamed version with 33 MHz processor
The ''Service Source'' has no Adjustments chapter; Apple publishes no rail tolerances or power-supply adjustment for this machine. Its troubleshooting chapter includes an error-chord chart as well as system, video, drive and peripheral charts.<ref name="ss650ts2">''Centris 650/Quadra 650 Service Source'', Troubleshooting, pp. 1-14 (PDF pp. 17-30).</ref>
* '''[[Macintosh Centris 610]]''' – Smaller desktop variant
* '''[[Macintosh IIvx]]''' – Uses same case design
* '''[[Macintosh IIvi]]''' – Earlier model in same case


== Service Documentation ==
== Documentation ==
* [[Centris 650/Quadra 650 Service Source]]: Apple's module-level service manual.
* [[Macintosh Centris 610 Centris 650 and Quadra 800 Developer Note]]: Apple's design description, with the power, RAM and SCSI details used above.


The official Apple Service Source documentation for this model:
== Related pages ==
 
* [[Macintosh Quadra 650]]
<pdf width="800" height="500">File:Quadra.centris_650.pdf</pdf>
* [[Macintosh Centris 610]]
 
* [[Macintosh IIvx]]
== See Also ==
* [[Retrobrite]]
 
* [[Macintosh Centris 650 General Maintenance]]
* [[Macintosh Centris 650 Troubleshooting]]
* [[Macintosh Centris 650 Capacitor Replacement Guide]]


== References ==
== References ==
Line 209: Line 123:


[[Category:Apple Vintage Computers]]
[[Category:Apple Vintage Computers]]
{{Navbox-AppleVintage|state=collapsed}}

Latest revision as of 15:24, 30 September 2026

Macintosh Centris 650
Centris 650 at the Apple Museum, Prague (photo: Benoît Prieur, CC0)
Specifications
ManufacturerApple Computer, Inc.
TypeDesktop personal computer
Released10 February 1993
Discontinued21 October 1993
Intro priceUS$2,700, $3,400 and $3,800 (three configurations)
CPUMotorola MC68040 @ 25 MHz (MC68LC040 in the entry model)
Memory4 or 8 MB on the logic board; four 72-pin SIMM slots; 132 or 136 MB maximum
Storage1.4 MB SuperDrive; 80–500 MB SCSI hard drive; optional internal CD-ROM
DisplayExternal monitor via DB-15; 512 KB VRAM, 1 MB maximum
Sound8-bit stereo output, mono input
ROM1 MB
ExpansionThree NuBus slots and one processor-direct slot
Power100–240 V AC, 112 W maximum
Dimensions152 × 330 × 419 mm (6.0 × 13.0 × 16.5 in) H × W × D
Weight11.3 kg (25 lb), varying with the drives fitted
OS / FirmwareSystem 7.1 – Mac OS 8.1
SuccessorMacintosh Quadra 650
Model no.M1205

The Macintosh Centris 650 is a desktop Macintosh with a 25 MHz Motorola 68040, three NuBus slots and a processor-direct slot. Apple introduced it on 10 February 1993, with the Macintosh Centris 610, and discontinued it on 21 October 1993.[1] It was replaced by the Macintosh Quadra 650, the same machine with a 33 MHz 68040; Apple services the two from one Service Source volume.[2] The case is the desktop design of the Macintosh IIvx and Performa 600.[3]

Configurations

[edit | edit source]
Centris 650 configurations (EveryMac)[1]
Order number Processor RAM VRAM Hard drive Other
M1207LL/A 68LC040 (no FPU) 4 MB 512 KB 80 MB
M1337LL/A 68040 8 MB 512 KB 230 MB Ethernet
M1279LL/A 68040 8 MB 1 MB 230 MB Ethernet, 2× CD-ROM

EveryMac gives US prices of $2,700, $3,400 and $3,800.[1]

Hardware

[edit | edit source]

Processor and memory

[edit | edit source]

The 68040 runs at 25 MHz with an integrated MMU and FPU; the entry configuration's 68LC040 has no FPU.[2][1] The developer note says a 68LC040 can be replaced by a 68040 in its socket.[4]

The logic board carries 4 or 8 MB of RAM. Four 72-pin SIMM slots take 80 ns or faster SIMMs of 4, 8, 16 or 32 MB, giving a maximum of 132 MB with 4 MB on the board or 136 MB with 8 MB.[5] The Service Source gives only the 132 MB figure.[2] ROM is 1 MB and PRAM 256 bytes.[2]

Video

[edit | edit source]

Built-in video drives one monitor from a DB-15 port, with 512 KB of VRAM expandable to 1 MB. VGA monitors are supported at 640 × 480 and SVGA at 800 × 600, with an adapter cable.[2]

Maximum colour depth by resolution[6]
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

Storage

[edit | edit source]

An internal 1.4 MB Apple SuperDrive, an 80 to 500 MB SCSI hard drive and an optional internal 5.25-inch CD-ROM drive.[2] The case holds two internal SCSI devices.[4] The external DB-25 SCSI port supports up to six devices; the computer is always SCSI device 7.[2] The drive at the end of the internal cable must be terminated and other internal devices must not; the logic board terminates the external end automatically when nothing is plugged in.[7]

Ports and expansion

[edit | edit source]

Two ADB ports (500 mA maximum for all devices), two mini DIN-8 serial ports (RS-232/RS-422), DB-25 SCSI, DB-15 video, stereo sound out, mono sound in, an Ethernet port on configurations that have it, three NuBus slots and one processor-direct slot.[2][1] Each of the three slots can supply 15 W to a card.[8]

Power

[edit | edit source]

Line voltage is 100–240 V AC at 50–60 Hz, and the maximum power is 112 W, not including the display.[2] The developer note describes the supply as the same physical size as the Quadra 700's, delivering up to 112 W, with 1.5 A at +5 V and 2.0 A at +12 V left for internal drives after the logic board and cards.[8] Apple's online technical specifications page for the Centris 650 gives 230 W, but that page describes the machine fitted with the Power Macintosh Upgrade Card.[6] The service part number of the supply is 661-0758.[9]

The clock and PRAM run from a 3.6 V lithium battery.[1] Apple's check is to measure it on the 10 V DC range and replace it below 3.2 V.[10]

Apple's symptom chart notes that thermal protection circuitry may shut the machine down if the air vents are blocked, and that it should recover after 30 to 40 minutes.[11]

Capacitors

[edit | edit source]

Retro Viator reports that the logic board of a Quadra 650, which Apple services alongside the Centris 650, carried tantalum capacitors and no aluminium electrolytics, while its power supply did contain electrolytics.[12] Check your own board before ordering parts. See Macintosh Centris 650 Capacitor Replacement Guide.

Upgrades

[edit | edit source]

A Power Macintosh card in the processor-direct slot converts the machine to PowerPC, and Apple offered a logic board upgrade to the Power Macintosh 7100/66 or 7100/66AV.[13]

Service parts

[edit | edit source]
Centris 650 / Quadra 650 service parts (Apple exploded view)[9]
Part Apple part number
Power supply 661-0758
Floppy drive 661-0121, 661-0474
Hard drive / CD-ROM SCSI cable 922-0053
Top cover 922-0405
Front panel 922-0542
Speaker 922-0055

The exploded view gives no logic board part number; it refers to a separate parts list.[9]

Maintenance and repair

[edit | edit source]

The Service Source has no Adjustments chapter; Apple publishes no rail tolerances or power-supply adjustment for this machine. Its troubleshooting chapter includes an error-chord chart as well as system, video, drive and peripheral charts.[14]

Documentation

[edit | edit source]
[edit | edit source]

References

[edit | edit source]
  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Apple Macintosh Centris 650 Specs, EveryMac.com—link(accessed 2026-09-30) Dates, configurations and order numbers, prices, model M1205, Gestalt ID 30, supported Mac OS 7.1–8.1, 3.6 V lithium battery.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Apple Computer, Centris 650/Quadra 650 Service Source, Specifications, pp. 1-11 (PDF pp. 5-15). Hosted as File:Quadra.centris_650.pdf; see Centris 650/Quadra 650 Service Source.
  3. ↑ Apple Computer, Developer Note: Macintosh Centris 610, Macintosh Centris 650, and Macintosh Quadra 800 Computers (1993), "Product Designs", p. 3 (PDF p. 15). Hosted as File:Macintosh Centris 610 Centris 650 and Quadra 800 Developer Note.pdf; see Macintosh Centris 610 Centris 650 and Quadra 800 Developer Note.
  4. ↑ 4.0 4.1 Developer Note: Centris 610, Centris 650, Quadra 800, Table 1-1, p. 3 (PDF p. 15).
  5. ↑ Developer Note: Centris 610, Centris 650, Quadra 800, "RAM", p. 21 (PDF p. 33).
  6. ↑ 6.0 6.1 Centris 650: Technical Specifications, Apple—link(accessed 2026-09-30) Apple's page describes the Centris 650 fitted with the Power Macintosh Upgrade Card (PowerPC 601, introduced 14 March 1994); its video, memory and physical figures apply to the base machine.
  7. ↑ Developer Note: Centris 610, Centris 650, Quadra 800, "SCSI Bus and Termination", pp. 18-19 (PDF pp. 30-31).
  8. ↑ 8.0 8.1 Developer Note: Centris 610, Centris 650, Quadra 800, "Power Supplies" and Table 1-3, p. 9 (PDF p. 21).
  9. ↑ 9.0 9.1 9.2 Centris 650/Quadra 650 Service Source, Exploded View (PDF p. 81).
  10. ↑ Centris 650/Quadra 650 Service Source, Additional Procedures, Battery Verification, pp. 1-2 (PDF pp. 60-61).
  11. ↑ Centris 650/Quadra 650 Service Source, Troubleshooting, Symptom Charts, System, p. 4 (PDF p. 20).
  12. ↑ Apple Macintosh Quadra 650, Retro Viator, 2021-09-02—link(accessed 2026-09-30)
  13. ↑ Centris 650/Quadra 650 Service Source, Upgrades, Power Macintosh Card and Power Macintosh Upgrade, pp. 9-12 (PDF pp. 76-79).
  14. ↑ Centris 650/Quadra 650 Service Source, Troubleshooting, pp. 1-14 (PDF pp. 17-30).