Macintosh Quadra 950
 | |
| Macintosh Quadra 950 | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Workstation / Personal Computer |
| Released | May 18, 1992 |
| Discontinued | October 14, 1995 |
| Intro price | US$8,500–$9,600 |
| CPU | Motorola 68040 @ 33 MHz |
| Memory | 8 MB or 16 MB RAM (expandable to 256 MB) |
| Storage | 230 MB, 400 MB, or 1 GB SCSI hard drive; 1.44 MB floppy |
| Display | 512×384 to 1152×870 (via onboard video) |
| Sound | 8-bit stereo audio |
| Dimensions | 18.6" × 8.9" × 20.6" (47.2 × 22.6 × 52.3 cm) |
| Weight | 36.8 lbs (11.5 kg) |
| OS / Firmware | System 7.0.1 – Mac OS 8.1 |
| Predecessor | Quadra 900 |
| Successor | Power Macintosh 9500 |
| Codename | N/A |
| Model no. | M4300 |
The Macintosh Quadra 950 is a high-end workstation computer introduced by Apple Computer on May 18, 1992.[1] It replaced the Quadra 900 and utilized the same large tower enclosure. The Quadra 950 featured a faster 33 MHz Motorola 68040 processor (up from 25 MHz in the 900), making it one of the most powerful 68k Macintoshes produced.[2]
The Quadra 950 was marketed toward professionals requiring maximum expandability and processing power. It remained in production for over three years until being replaced by the Power Macintosh 9500 in 1995. Apple also sold a server variant, the Workgroup Server 95, based on the same hardware.
Architecture and Processor
The Quadra 950 is built around the Motorola 68040 processor running at 33 MHz with an integrated floating-point unit (FPU).[3] The 68040 features an 8 KB instruction cache and 8 KB data cache. The system bus also runs at 33 MHz.
| Component | Specification |
|---|---|
| Processor | Motorola 68040 @ 33 MHz |
| FPU | Integrated (68040) |
| L1 Cache | 8 KB (4 KB instruction + 4 KB data) |
| System Bus | 33 MHz |
| ROM | 1 MB |
| Gestalt ID | 26 |
Memory and Storage
RAM Configuration
The Quadra 950 shipped with either 8 MB or 16 MB of RAM. It has 16 30-pin SIMM slots supporting up to 256 MB of RAM using third-party 16 MB SIMMs, though Apple officially supported a maximum of 64 MB.[4] RAM must be installed in matched groups of four identical SIMMs.
| Specification | Value |
|---|---|
| RAM Type | 30-pin SIMM |
| Minimum Speed | 80 ns |
| Standard RAM | 8 MB or 16 MB |
| Maximum RAM | 256 MB (with 16× 16 MB SIMMs) |
| SIMM Slots | 16 (install in groups of 4) |
Storage Systems
Storage options included SCSI hard drives of 230 MB, 400 MB, or 1 GB capacity. The system includes a 1.44 MB SuperDrive floppy and an optional internal 2× CD-ROM drive. The tower case provides three internal 5.25" drive bays (two front-accessible if no CD-ROM is installed).
Display and Graphics
The Quadra 950 includes onboard video with 1 MB of VRAM, expandable to 2 MB via four 80 ns VRAM SIMM slots. Video capabilities depend on VRAM configuration:
| VRAM | Resolution | Color Depth |
|---|---|---|
| 1 MB | 512×384 | 24-bit (millions) |
| 1 MB | 640×480, 832×624, 1152×870 | 8-bit (256 colors) |
| 2 MB | 832×624 | 24-bit (millions) |
| 2 MB | 1152×870 | 8-bit (256 colors) |
Additional displays can be supported via NuBus video cards.
Input/Output and Expansion
Port Configuration
| Port | Type | Quantity |
|---|---|---|
| Serial | Mini DIN-8 | 2 (Modem, Printer) |
| SCSI | DB-25 | 1 |
| ADB | Mini DIN-4 | 2 |
| Floppy | DB-19 | 1 |
| Audio In | 3.5mm stereo | 1 |
| Audio Out | 3.5mm stereo | 1 |
| Ethernet | AAUI-15 | 1 |
Expansion Slots
The Quadra 950 offers extensive expansion capability:
- 5 NuBus slots — Three provide 15W of power; two provide 25W
- 1 Processor Direct Slot (PDS) — 68040 PDS for accelerator cards
The tower case accommodates up to three internal drive bays.
General Maintenance
For detailed maintenance practices including cleaning, PRAM battery management, and connector corrosion prevention, refer to the dedicated Macintosh Quadra 900 General Maintenance page. The Quadra 950 shares the same case and many components with the Quadra 900.
PCB Schematics & Service Manual
The Macintosh Quadra 950 shares its service documentation with the Quadra 900 and Workgroup Server 95.
Apple Service Manual
All Apple Service Manuals can be found on the Apple Service Source page.
Capacitor Replacement Guide
Detailed capacitor replacement guidelines can be found on the Macintosh Quadra 900 Capacitor Replacement Guide page. The Quadra 950 uses the same logic board design as the Quadra 900.
Retrobrite
To address plastic yellowing, detailed instructions can be found on the Retrobrite page.
Troubleshooting
A comprehensive troubleshooting guide addressing power issues, video problems, and common failures is available on the Macintosh Quadra 900 Troubleshooting page.
Technical Details
System Architecture at a Glance
| Sub-system | Specification (Macintosh Quadra 950, 1992) |
|---|---|
| CPU | Motorola 68040 @ 33 MHz |
| FPU | Integrated |
| Bus width | 32-bit data • 32-bit address |
| ROM | 1 MB |
| RAM | 8–256 MB (16 SIMM slots) |
| VRAM | 1–2 MB |
| Video | 512×384 to 1152×870 |
| Sound | 8-bit stereo |
| Storage | SCSI (230 MB–1 GB), 1.44 MB floppy |
| Expansion | 5 NuBus, 1 PDS |
| Networking | AAUI-15 Ethernet |
| Power | 100–240V AC, 303W max |
Service Documentation
The official Apple Service Source documentation for this model: