RetroTechCollection

Macintosh Centris 650

Revision as of 15:24, 30 September 2026 by Josh (talk | contribs) (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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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]

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

Configurations

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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

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Processor and memory

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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

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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

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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

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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

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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

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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

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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

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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

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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

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References

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  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).


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