Macintosh Quadra 950

The logic board has five NuBus slots and a Processor Direct Slot, but due to the positioning of the PDS it is not possible to use one of the NuBus slots when a PDS card is installed. This feature was also shared with the preceding Quadra 700 and 900 and upcoming Quadra 840AV. 24-bit color support was removed from newer Quadra and Centris models as a cost-saving measure although 24-bit color could be enabled in these models with a video card. The 950 includes a key to limit access to various subsystems depending on the computer's use environment. The key switch has three positions labelled OFF, ON and SECURE. The OFF position immediately cuts the power and prevents the computer from being powered on. The ON position allows the computer to operate normally. The SECURE position is intended for use as a server – power is always applied in this position. If the computer loses power, it immediately starts up when power is restored. Also, this position disables the keyboard, mouse and floppy disk drive. The Workgroup Server 95 models include the Workgroup Server PDS Card which provides two SCSI controllers with two internal SCSI connectors (plus one external connector), a direct memory access controller for SCSI transfers to reduce I/O load on the main CPU, and 128 KB of SRAM used as an L2 cache and expandable using three additional slots to a total of 512 KB. Described as "a Quadra 950 with some minor, but important, modifications", these modifications enabled file transfers at speeds ranging from twice as fast to nine times as fast as the earlier system. Particularly important was A/UX's "excellent use of a disk cache", in contrast to the "horrendous speed penalties" of disk caching under System 7. == Models ==

The Quadra 950 was announced on March 18, with dealers receiving machines around May 18. Introduced May 18, 1992: • Macintosh Quadra 950: 33 MHz 68040 CPU. $7,200 for a floppy drive only model, $8,499 with a 230 MB HDD, and $9,199 with a 400 MB HDD. In the United States, the configurations were split into "File and Print" and "Database" configurations: • File/Print: 16 MB RAM, 230 MB HDD, 128 KB L2 cache. $7,589. • File/Print: 16 MB RAM, 500 MB HDD, DDS-DC digital tape drive, 256 KB L2 cache. $10,039. • File/Print: 32 MB RAM, 1000 MB HDD, DDS-DC digital tape drive, AppleShare Pro, 512 KB L2 cache. $12,839. • Database: 32 MB RAM, 230 MB and 500 MB HDDs, DDS-DC digital tape drive, 256 KB L2 cache. $11,319. • Database: 48 MB RAM, 230 MB and 1000 MB HDDs, DDS-DC digital tape drive, 512 KB L2 cache. $12,929. == Specifications ==

• Processor: 33 MHz Motorola 68040 • Processor Cache: 8 KB Level 1 • Bus Speed: 33 MHz • Hard Drive: 230 MB – 1 GB • Media drives: 1.44 MB floppy drive, optional DDS-DC drive (Workgroup Server 95) • Software: Mac OS 7.1 – 8.1 • Logicboard RAM: None • Maximum RAM: 256 MB • Type of RAM: 30-pin SIMM (16 slots) • Minimum RAM Speed: 80 ns • Interleaving Support: No • Graphics: Integrated • Display Connection: DB-15 • Graphics Memory: 1 MB standard, upgradable to 2 MB via 4 VRAM slots • Expansion Slots: 5 - NuBus, 1 - PDS • Hard Drive Bus: SCSI • Backup Battery: 3.6 V Lithium • Max Watts: 303 W • Ports: AAUI-15 Ethernet, 1 ADB, DB-25 SCSI, 2 Serial, 3.5-mm mono input jack, 3.5-mm stereo output jack ==Notable uses==

AnimEigo upgraded their subtitling hardware to this model during the mid-1990s. American industrial rock band Nine Inch Nails used the Quadra 950 during the recording of their album The Fragile, utilising its NuBus expansion slots for Pro Tools I/O cards. ==Timelines==