Macintosh Centris 660AV
 | |
| Macintosh Centris 660AV | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Personal Computer |
| Released | July 29, 1993 |
| Discontinued | September 12, 1994 |
| Intro price | US$2,300 |
| CPU | Motorola 68040 @ 25 MHz |
| Memory | 8 MB RAM (expandable to 68 MB) |
| Storage | 230 MB or 500 MB SCSI hard drive |
| Display | Supports 512×384 to 1152×870 |
| Sound | 16-bit stereo input/output |
| Dimensions | 3.4" × 16.3" × 15.6" (8.6 × 41.4 × 39.6 cm) |
| Weight | 14.0 lbs (6.4 kg) |
| OS / Firmware | System 7.1 – Mac OS 8.1 |
| Predecessor | Macintosh Centris 610 |
| Successor | Power Macintosh 6100 |
| Codename | Tempest |
| Model no. | M9040 |
The Macintosh Centris 660AV is a personal computer designed, manufactured, and sold by Apple Computer from July 1993 to September 1994.[1] It was introduced alongside the Macintosh Quadra 840AV; the "AV" designation signifies video input and output capabilities and enhanced audio processing. The machine was rebranded as the Macintosh Quadra 660AV in October 1993 without any internal hardware changes.[2]
Model Variants
[edit | edit source]The Centris 660AV and Quadra 660AV are identical machines with different nameplates. Apple discontinued the Centris line in October 1993, rebranding remaining inventory as Quadra. Configurations included:
- M1839LL/A – 230 MB hard drive
- M9043LL/A – 230 MB hard drive with 2× CD-ROM
- M9044LL/A – 500 MB hard drive
- M1840LL/A – 500 MB hard drive with 2× CD-ROM
Architecture and Processor
[edit | edit source]The 660AV uses a full Motorola 68040 processor running at 25 MHz with an integrated FPU, unlike the Macintosh Centris 610 which uses the FPU-less 68LC040.[3] The clock input runs at 50 MHz, but the processor itself is not clock-doubled.
AT&T DSP 3210
[edit | edit source]The 660AV includes an AT&T 3210 digital signal processor clocked at 55 MHz. This DSP handles multimedia functions including:
- Real-time speech recognition (PlainTalk)
- Audio processing and effects
- Video compression/decompression
- Telephony functions via GeoPort
The DSP reduces CPU load during video capture and playback operations.
ROM
[edit | edit source]The 660AV introduced a new 2 MB universal ROM (codenamed "SuperMario") that would later be used in all PowerPC systems.[4] This ROM includes:
- SCSI Manager 4.3
- Sound Manager 3.0
- Vectorized code for easier patching
Memory and Storage
[edit | edit source]RAM Configuration
[edit | edit source]| Specification | Details |
|---|---|
| Onboard RAM | 4 MB soldered |
| SIMM Slots | 2 (72-pin) |
| Standard RAM | 8 MB |
| Maximum RAM | 68 MB |
| SIMM Speed | 70 ns or faster |
| SIMM Types | 4 MB, 8 MB, 16 MB, or 32 MB (64 MB SIMMs not supported) |
Storage Systems
[edit | edit source]The 660AV uses an internal SCSI hard drive (230 MB or 500 MB depending on configuration). The SCSI direct-memory access chip combined with SCSI Manager 4.3 provides improved disk performance compared to earlier Quadra models.
Display and Graphics
[edit | edit source]The 660AV has 1 MB of dedicated 80 ns DRAM for video, which cannot be upgraded.
| Resolution | Color Depth |
|---|---|
| 512×384, 640×400 | 24-bit (millions) |
| 640×480, 800×600, 832×624 | 16-bit (thousands) |
| 1024×768, 1152×870 | 8-bit (256 colors) |
A second display can be supported with the addition of a compatible PDS or NuBus video card.
Audio Capabilities
[edit | edit source]The 660AV features 16-bit stereo audio input and output. The AT&T DSP enables:
- PlainTalk speech recognition
- Text-to-speech synthesis
- Real-time audio effects processing
- CD-quality recording and playback
GeoPort
[edit | edit source]The 660AV is the first Macintosh to include GeoPort, a high-speed serial port technology.[5] With an optional GeoPort Telecom Adapter, the 660AV can function as a fax machine and modem using software and the DSP rather than dedicated modem hardware.
Video Input/Output
[edit | edit source]The 660AV includes built-in video digitizing capabilities:
- S-Video input and output
- Composite video input and output (RCA)
- Audio/video connector on rear panel
Note: The 660AV does not support video mirroring. When outputting to TV or VCR, the computer monitor will be blank.
Input/Output and Expansion
[edit | edit source]Port Configuration
[edit | edit source]| Port Type | Quantity | Notes |
|---|---|---|
| ADB | 2 | Keyboard and mouse |
| GeoPort Serial | 2 | Printer and modem (DIN-8) |
| SCSI | 1 | DB-25 |
| Ethernet | 1 | AAUI-15 |
| S-Video In/Out | 1 each | |
| Composite Video In/Out | 1 each | RCA |
| Audio In/Out | Stereo | 3.5mm |
Expansion Slots
[edit | edit source]- 1 PDS slot (Processor Direct Slot)
- Optional 7" NuBus slot via PDS-to-NuBus adapter (M9049LL/A), includes DAV connector support
Design and Features
[edit | edit source]The 660AV uses the same "pizza box" desktop case as the Macintosh Centris 610. Early Centris 660AV units have an auto-inject floppy drive similar to the 610, while later Centris models and all Quadra 660AV units have a manual-inject drive with a round indentation at the center of the slot.
Power Supply
[edit | edit source]- Input: 100V–240V AC, 50–60 Hz
- Maximum power: 86 watts
General Maintenance
[edit | edit source]For detailed maintenance practices including cleaning, PRAM battery management, connector corrosion prevention, and voltage adjustments, refer to the dedicated Macintosh Centris 660AV General Maintenance page.
Capacitor Replacement Guide
[edit | edit source]Detailed capacitor replacement guidelines for the logic board can be found on the Macintosh Centris 660AV Capacitor Replacement Guide page.
Troubleshooting
[edit | edit source]A comprehensive troubleshooting guide addressing no power, no video, intermittent operation, and other common problems is available on the Macintosh Centris 660AV Troubleshooting page.
Technical Details
[edit | edit source]System Architecture at a Glance
[edit | edit source]| Sub-system | Specification |
|---|---|
| CPU | Motorola 68040 @ 25 MHz |
| DSP | AT&T 3210 @ 55 MHz |
| Bus width | 32-bit data • 32-bit address |
| ROM | 2 MB (SuperMario) |
| RAM | 8 MB standard (expandable to 68 MB) |
| VRAM | 1 MB dedicated |
| Video | Up to 1152×870 @ 8-bit |
| Sound | 16-bit stereo, 44.1 kHz |
| Disks | 1.44 MB floppy, SCSI hard drive |
| Optical | 2× CD-ROM (optional) |
| Ports | ADB ×2, GeoPort Serial ×2, SCSI, AAUI Ethernet, Video I/O |
Processor Specifications
[edit | edit source]| Component | Specification |
|---|---|
| CPU | Motorola 68040 @ 25 MHz |
| FPU | Integrated |
| DSP | AT&T 3210 @ 55 MHz |
| Data Bus | 32-bit |
| Address Bus | 32-bit |
| L1 Cache | 8 KB (4 KB instruction + 4 KB data) |
| System Bus | 25 MHz |
Upgrades
[edit | edit source]Apple offered a Power Macintosh Upgrade Card for US$1,399 that upgraded the 660AV to match the Power Macintosh 6100/60AV specifications. Third-party accelerators include:
- MicroMac Speedy variable speed oscillator (up to 29 MHz)
- Sonnet QuadDoubler (50 MHz 68040)
- MicroMac slot-free 128 KB L2 cache
Known Issues
[edit | edit source]- The Startup Disk control panel in System 7.5–7.5.3 is incompatible with Quadra AVs. System 7.5.5 fixes this issue.
- Quadra AVs do not support 24-bit addressing mode.
- A "fat" (universal) system must be installed to use a PowerPC upgrade card.
- A dead or low-voltage PRAM battery can cause loss of built-in video.
Tip: Hold Cmd-Opt-T-V during startup to force the Mac to use a TV as a monitor.
Service Documentation
[edit | edit source]The official Apple Service Source documentation for this model:
See Also
[edit | edit source]References
[edit | edit source]- ↑ Macintosh Centris 660AV Specs, EveryMac.com—link(accessed 2026-02-10)
- ↑ Macintosh Quadra 660AV, Wikipedia—link(accessed 2026-02-10)
- ↑ Macintosh Quadra 660AV: Technical Specifications, Apple—link(accessed 2026-02-10)
- ↑ Centris 660AV & Quadra 840AV: 2MB ROM Information, Apple—link(accessed 2026-02-10)
- ↑ Centris 660av (Quadra 660av), Low End Mac—link(accessed 2026-02-10)