Macintosh Quadra 605
The Macintosh Quadra 605 is a personal computer designed and sold by Apple Computer, Inc. from October 1993 to July 1996. The model names reflect a decision made at Apple in 1993 to follow an emerging industry trend of naming product families for their target customers – Quadra for business, LC for education, Performa for home. Accordingly, the Performa 475 and 476 was sold in department stores and electronics stores such as Circuit City, whereas the Quadra was purchased through an authorized Apple reseller; when introduced, the Quadra 605 was the least expensive new computer in Apple's lineup. The Quadra 605 reuses the Macintosh LC III's pizza box form factor with minor modifications; the Quadra 605 was discontinued in October 1994, the LC 475 variant continued to be sold to schools until July 1996. Apple offered no direct replacement for these machines, making it the final Macintosh to use the LC's lightweight slim-line form factor. Apple would not release another desktop computer under 10 pounds until the Mac Mini, nearly ten years later.
All models come standard with a 68LC040 CPU running at 25 MHz, 4 MB RAM on board, 512 KB of VRAM, 1 LC III-style Processor Direct Slot, 1 ADB and 2 serial ports, external SCSI port, a manual-inject floppy drive. Introduced October 18, 1993: Macintosh Performa 475: 4 MB RAM, 160 MB HDD. Bundled with a keyboard and Apple Color Plus 14" Display. Macintosh Performa 476: 4 MB RAM, 230 MB HDD. Bundled with a keyboard and Apple Color Plus 14" Display. Introduced October 21, 1993: Macintosh Quadra 605: 4 MB RAM, 80 MB HDD. Different case design, the only variant that does not have a case screw. Not available in Europe. Macintosh LC 475: 4 MB RAM, 80 MB HDD. Bundled with a keyboard and optionally with an Apple Macintosh Color Display. Central processing unit: 25 MHz MC68LC040, 32-bit bus. 8 KB of on-chip L1 cache is divided into 4 KB of instruction cache. There are no other caches; the 68LC040 can be replaced with a 68040. This will triple the speed of floating point operations. Random access memory: 4 MB on the motherboard, one 72-pin SIMM socket for 80 ns or faster SIMMs.
The official supported maximum RAM is 36 MB in one 32 MB 72-pin SIMM plus 4 MB on the motherboard, but larger SIMMs do work—up to 128 MB may be used, with some limits on RAM type. Physical limits might apply if the side of the SIMM facing the CPU has thicker chips, as the clips on the SIMM socket will not close around it automatically, it should be possible to manually push the clips enough to hold the SIMM in place. The DJMEMC memory controller used in the Quadra 605's predecessors will only recognize SIMMs up to 32 MB, while the newer MEMCjr used in the Quadra 605 recognizes the larger sizes. Video: Video out is provided by one DA15F connector, is compatible with VGA monitors through the use of an adaptor. Two internal Video RAM slots can take either two 256 KB 80 ns 68-pin VRAM SIMMs, or two 512 KB SIMMs. Installing one 512 KB and one 256 KB VRAM SIMM garbles the display. Resolutions and colors available with the two VRAM configurations are shown in the table below: Audio: Out: stereo 8-bit, 11 kHz or 22 kHz.
The input socket is a stereo socket, can input two channels of a stereo signal—however, these are mixed and only accessible to the hardware as a combined mono 8-bit signal. An Apple PlainTalk Microphone provides line-level input by using a longer 4-contact plug which receives power from a 5 V supply within the input jack. Other microphones only give a mic-level input, do not work with the Quadra 605. Recording is possible at 11,000 or 22,000 samples/second, with filters applied at 3.5 kHz and 7 kHz while recording. Floppy Drive: 1.4 MB SuperDrive, manual-inject. Hard Drive: 80 MB, 160 MB or 230 MB SCSI hard drive, depending on model. Battery: Quadra 605s take a lithium half-AA cell 3.6 V battery. If the battery is drained, the video will not start up. To start up a Quadra 605 with a flat or missing battery, it can be turned on for a few seconds turned off for a second on again; this leaves enough charge in the system's capacitors for video to start up. Power supply: 30 watts standard, but many second-hand machines come with replacement PSUs, either third-party, Apple replacement, or stripped from earlier LC models.
Some of these go up to 45 watts. The Quadra 605 is a registered Energy Star-Compliant product. Weight: 8.8 lb / 4 kg standard. A Quadra 605 can support a monitor up to 35 lb / 15.9 kg. Dimensions: 2.9" high x 12.2" wide x 15.3" deep / 7.4 cm high x 31 cm wide x 38.8 cm deep. The Quadra 605 contains. While this is mechanically compatible with previous models' LC PDS it is not a true LC PDS, but emulates the previous machine's 68030 slot. Due to the success of the LC PDS in earlier Macs and with many expansion options manufactured, Apple kept the same slot type in these 68040 machines. While the Quadra 605's LC PDS is 68030-compatible, expansion cards made for'030 processors, such as 68881 or 68882 FPUs, will not work. In addition it can utilize the Apple IIe Card; the Quadra 605 has one SCSI bus, with a 50-pin internal connector (with space for one low-profile 3.5" SC
Apple Computer 1 known as the Apple I, or Apple-1, is a desktop computer released by the Apple Computer Company in 1976. It was hand-built by Steve Wozniak. Wozniak's friend Steve Jobs had the idea of selling the computer; the Apple I was Apple's first product, to finance its creation, Jobs sold his only motorized means of transportation, a VW Microbus, for a few hundred dollars, Steve Wozniak sold his HP-65 calculator for $500. It was demonstrated in July 1976 at the Homebrew Computer Club in California. Production was discontinued on September 30, 1977, after the June 10, 1977 introduction of its successor, the Apple II, which Byte magazine referred to as part of the "1977 Trinity" of personal computing. On March 5, 1975, Steve Wozniak attended the first meeting of the Homebrew Computer Club in Gordon French's garage, he was so inspired that he set to work on what would become the Apple I computer. After building it for himself and showing it at the Club, he and Steve Jobs gave out schematics for the computer to interested club members and helped some of them build and test out copies.
Steve Jobs suggested that they design and sell a single etched and silkscreened circuit board—just the bare board, with no electronic parts—that people could use to build the computers. Wozniak calculated that having the board design laid out would cost $1,000 and manufacturing would cost another $20 per board. To fund this small venture—their first company—Jobs sold his van and Wozniak sold his HP-65 calculator. Soon after, Steve Jobs arranged to sell "something like 50" built computers to the Byte Shop at $500 each. To fulfill the $25,000 order, they obtained $20,000 in parts at 30 days net and delivered the finished product in 10 days; the Apple I went on sale in July 1976 at a price of US$666.66, because Wozniak "liked repeating digits" and because of a one-third markup on the $500 wholesale price. The first unit produced was used in a high school math class, donated to Liza Loop's public-access computer center. About 200 units were produced, all but 25 were sold within nine or ten months.
The Apple I's built-in computer terminal circuitry was distinctive. All one needed was a television set. Competing machines such as the Altair 8800 were programmed with front-mounted toggle switches and used indicator lights for output, had to be extended with separate hardware to allow connection to a computer terminal or a teletypewriter machine; this made the Apple I an innovative machine for its day. In April 1977, the price was dropped to $475, it continued to be sold through August 1977, despite the introduction of the Apple II in April 1977, which began shipping in June of that year. In October 1977, the Apple I was discontinued and removed from Apple's price list; as Wozniak was the only person who could answer most customer support questions about the computer, the company offered Apple I owners discounts and trade-ins for Apple IIs to persuade them to return their computers. These recovered boards were destroyed by Apple, contributing to their rarity today; as of 2013, sixty-three Apple I computers have been confirmed to exist.
Only six have been verified to be in working condition. The Apple-1 Registry lists every known Apple I computer; this registry serves an additional purpose by including a list of all auctions since 2000. An Apple I sold for US$50,000 at auction in 1999. In 2008, the website Vintage Computing and Gaming reported that Apple I owner Rick Conte was looking to sell his unit and was "expecting a price in excess of $15,000 U. S." The site reported Conte had donated the unit to the Maine Personal Computer Museum in 2009. A unit was sold in September 2009 for $17,480 on eBay. A unit belonging to early Apple Computer engineers Dick and Cliff Huston was sold on March 23, 2010, for $42,766 on eBay. In November 2010, an Apple I sold for £133,250 at Christie's auction house in London; the high price was due to the rare documents and packaging offered in the sale in addition to the computer, including the original packaging, a typed and signed letter from Jobs, the original invoice showing "Steven" as the salesman.
The computer was brought to Polytechnic University of Turin where it was fixed and used to run the BASIC programming language. On June 15, 2012, a working Apple I was sold at auction by Sotheby's for a then-record $374,500, more than double the expected price; this unit is on display at the Nexon Computer Museum in South Korea. In October 2012, a non-working Apple I from the estate of former Apple Computer employee Joe Copson was put up for auction by Christie's, but found no bidder, willing to pay the starting price of US$80,000. Copson's board had been listed on eBay in December 2011, with a starting bid of $170,000 and failed to sell. Following the Christie's auction, the board was restored to working condition by computer historian Corey Cohen. Copson's Apple I was once again listed on eBay, where it sold for US$236,100.03 on April 23, 2015. On November 24, 2012, a working Apple I was sold at auction by Auction Team Breker for €400,000. On May 25, 2013, a functioning 1976 model was sold for a then-record €516,000 in Cologne.
Auction Team Breker said "an unnamed Asian
The Macintosh 512K is a personal computer, designed and sold by Apple Computer, inc. from September 1984 to April 1986. It is the first update to the original Macintosh 128K, it was identical to the previous Macintosh, differing in the amount of built-in random-access memory. The increased memory turned the Macintosh into a more business-capable computer and gained the ability to run more software; the Mac 512K shipped with Macintosh System 1.1 but was able to run all versions of Mac OS up to System 4.1. It was replaced by the Macintosh Plus. All support for the Mac 512K was discontinued on September 1, 1998. Like the Macintosh 128K before it, the 512K contained a Motorola 68000 connected to a 512 kB DRAM by a 16-bit data bus. Though the memory had been quadrupled, it could not be upgraded; the large increase earned it the nickname Fat Mac. A 64 kB ROM chip boosts the effective memory to 576 kB, but this is offset by the display's 22 kB framebuffer, shared with the DMA video controller; this shared arrangement reduces CPU performance by up to 35%.
It shared a revised logic board with the re-badged Macintosh 128K. The resolution of the display was the same, at 512x342. Apple sold a memory upgrade for the Macintosh 128K for $995 and reduced the price when 256K DRAM prices fell months later; the applications MacPaint and MacWrite were still bundled with the Mac. Soon after this model was released, several other applications became available, including MacDraw, MacProject, Macintosh Pascal and others. In particular, Microsoft Excel, written for the Macintosh, required a minimum of 512 kB of RAM, but solidified the Macintosh as a serious business computer. Models with the enhanced ROM supported Apple's Switcher, allowing cooperative multitasking among applications; the LaserWriter printer became available shortly after the 512K's introduction, as well as the number pad, tablet, mouse, basic mouse, much more. It utilized Apple's built-in networking scheme LocalTalk which allows sharing of devices among several users; the 512K was the oldest Macintosh capable of supporting Apple's AppleShare built-in file sharing network, when introduced in 1987.
The expanded memory in the 512K allowed it to better handle large word-processing documents and make better use of the graphical user interface and increased speed over the 128K model. The original 512K could accept Macintosh system software up to version 4.1. An updated version replaced the Macintosh 512K and debuted as the Macintosh 512K enhanced in April 1986, it differed from the original 512K in that it had an 800 kB floppy disk drive and the same improved ROM as the Macintosh Plus. With the exception of the new model number, they were otherwise cosmetically identical; the stock 512K could use an 800 kB floppy disk drive as well as the Hard Disk 20, the first hard disk manufactured by Apple for use with the 512K, but required a special system file that loaded the improved ROM code into RAM, thus reducing the available RAM for other uses. Apple offered an upgrade kit which replaced the floppy disk drive and ROMs turning it into a 512Ke. One further OEM upgrade replaced the logicboard and the rear case with that of the Macintosh Plus.
As with the original Macintosh, the 512K was designed with no slots for upgrade boards and had no hard-disk controller, so the few internal upgrades that were available for the 512K, such as General Computer's US$2,795 Hyperdrive hard drive, had to plug directly into the 68000 processor socket. Other such upgrades included "snap-on" SCSI cards and RAM upgrades of 2 MB or more. Macintosh 128K/512K technical details Macintosh 512K technical specifications at apple.com Inside the Macintosh 512K
The Macintosh SE is a personal computer designed and sold by Apple Computer, Inc. from March 1987 to October 1990. It marked a significant improvement on the Macintosh Plus design and was introduced by Apple at the same time as the Macintosh II; the SE retains the same Compact Macintosh form factor as the original Macintosh computer introduced three years earlier and uses the same design language used by the Macintosh II. An enhanced model, the SE/30 was introduced in January 1989; the Macintosh SE was updated in August 1989 to include a SuperDrive, with this updated version being called the "Macintosh SE FDHD" and the "Macintosh SE SuperDrive". The Macintosh SE was replaced with the Macintosh Classic, a similar model which retained the same central processing unit and form factor, but at a lower price point; the Macintosh SE was introduced at the AppleWorld conference in Los Angeles on March 2, 1987. The "SE" is an acronym for "System Expansion", its notable new features, compared to its similar predecessor, the Macintosh Plus, were: First compact Macintosh with an internal drive bay for a hard disk or a second floppy drive.
First compact Macintosh. First Macintosh to support the Apple Desktop Bus only available on the Apple IIGS, for keyboard and mouse connections. Improved SCSI support with a standard 50-pin internal SCSI connector. Better reliability and longer life expectancy due to the addition of a cooling fan. Upgraded video circuitry that results in a lower percentage of CPU time being spent drawing the screen. In practice this results in a 10-20 percent performance improvement. Additional fonts and kerning routines in the Toolbox ROM Disk First Aid is included on the system diskThe SE and Macintosh II were the first Apple computers since the Apple I to be sold without a keyboard. Instead the customer was offered the choice of the new ADB Apple Keyboard or the Apple Extended Keyboard. Apple produced ten SEs with transparent cases as prototypes for promotional employees, they are rare and command a premium price for collectors. The Macintosh SE shipped with System 4.0 and Finder 5.4. The README file included with the installation disks for the SE and II is the first place Apple used the term "Macintosh System Software", after 1998 these two versions were retroactively given the name "Macintosh System Software 2.0.1".
Processor: Motorola 68000, 8 MHz, with an 8 MHz system bus and a 16-bit data path RAM: The SE came with 1 MB of RAM as standard, is expandable to 4 MB. The logic board has four 30-pin SIMM slots. Video: There is 256 KB of onboard video memory, enabling 512x384 monochrome resolution; the built-in screen has a lower resolution. Storage: The SE can accommodate either one or two floppy drives, or a floppy drive and a hard drive. After-market brackets were designed to allow the SE to accommodate two floppy drives as well as a hard drive, however it was not a configuration supported by Apple. In addition an external floppy disk drive may be connected, making the SE the only Macintosh besides the Macintosh Portable and Macintosh II which could support three floppy drives, though its increased storage, RAM capacity and optional internal hard drive rendered the external drives less of a necessity than for its predecessors. Single-floppy SE models featured a drive-access light in the spot where the second floppy drive would be.
Hard-drive equipped models came with a 20 MB SCSI hard disk. Battery: Located on the logic board is a 3.6 V lithium battery, which must be present in order for basic settings to persist between power cycles. Macintosh SE machines which have sat for a long time have experienced battery corrosion and leakage, resulting in a damaged case and logic board. Expansion: A Processor Direct Slot on the logic board allows for expansion cards, such as accelerators, to be installed; the SE can be upgraded to more than 5 MB with the MicroMac accelerators. In the past other accelerators were available such as the Sonnet Allegro. Since installing a card required opening the computer's case and exposing the user to high voltages from the internal CRT, Apple recommended that only authorized Apple dealers install the cards. Upgrades: After Apple introduced the Macintosh SE/30 in January, 1989, a logic board upgrade was sold by Apple dealers as a high-cost upgrade for the SE, consisting of a new SE/30 motherboard, case front and internal chassis to accommodate the upgrade components.
Easter egg: The Macintosh SE ROM size increased from 64 KB in the original Mac to 256 KB, which allowed the development team to include an Easter Egg hidden in the ROMs. By jumping to address 0x41D89A or reading from the ROM chips it is possible to display the four images of the engineering team. Introduced March 2, 1987: Macintosh SEIntroduced August 1, 1989: Macintosh SE FDHD: Includes the new SuperDrive, a floppy disk drive that can handle 1.4 MB High Density floppy disks. FDHD is an acronym for "Floppy Disk High Density". High-density floppies would become the de facto standard on both the Macintosh and PC computers from on. An upgrade kit was sold for the original Macintosh SE which included new ROM chips and a new disk controller chip, to replace the originals. Macintosh SE 1/20: The name of the Macintosh SE FD
The Apple Mouse began as one of the first commercial mice available to consumers. Over the years Apple has maintained a distinct form and function with its mice that reflects its design philosophies. Mice manufactured by Apple emphasize use of a single button control interface, it was not until 2005 that Apple introduced a mouse featuring a scroll ball and four programmable "buttons."All mice made by Apple contained a ball-tracking control mechanism until 2000, when Apple introduced optical LED-based control mechanisms. Apple's latest mouse uses laser tracking. In 1979, Apple was planning a business computer and arranged a visit with Xerox Parc research center to view some of their experimental technology, it was there they discovered the mouse, invented by Douglas Engelbart while he was working at SRI International. During an interview, Engelbart said "SRI patented the mouse, but they had no idea of its value; some years it was learned that they had licensed it to Apple for something like $40,000."
Apple was so inspired by the mouse they scrapped their current plans and redesigned everything around the mouse and GUI. One of the biggest problems was that the three button Xerox mouse cost over US$400 to build, not practical for a consumer-based personal computer. Apple commissioned Hovey-Kelley Design to assist them with the mouse design, which not only had to be redesigned to cost US$25 instead of US$400, but needed to be tested with real consumers outside a laboratory setting to learn how people were willing to use it. Hundreds of prototypes Apple settled on a single button mouse the size of a deck of cards. With the design complete, the operating system was adapted to interface with the single button design using keystrokes in combination with button clicks to recreate some of the features desired from the original Xerox three-button design. With the single button mouse design established for 25 years, the history of the Apple Mouse is a museum of design and ergonomics; the original mouse was a rectangular block of varying beige and gray color and profile for about a decade.
Not much it was redesigned to be angular along the top. In 1993 Apple redesigned the package to be egg-shaped, copied throughout the industry, it was still a tool available only in corporate gray or black. With the release of the iMac in 1998 the mouse became available in an array of translucent colors. Apple completed the transition to a circular design. Two years Apple switched back to a more elliptical shape and monochromatic black and white design; the rubber ball tracking mechanism was updated with a solid-state optical system, its single button was moved out of sight to the bottom of the mouse. Keeping up with the technological trends Apple went wireless in 2003 and two years though maintaining its iconic design style, broke its most controversial implementation in the mouse concept and for the first time released a “none button” mouse with five programmable electrostatic sensors and an integrated scroll ball. Though the Macintosh aftermarket had provided these options to discerning users for decades, Apple itself only made them complementary with its offerings after the passage of much time.
All of Apple's Bluetooth mice have cross-compatibility with every Bluetooth capable computer, though they are not supported by Apple for use on PCs. Apple's USB mice are compatible with nearly all USB equipped machines. Prior to USB, Apple created the Apple Desktop Bus interface. Though some other manufacturers licensed Apple's technology and ADB mice were interchangeable between them, the mouse interface IBM introduced on the PS/2 came to dominate the market and crushed all competition. ADB-to-PS/2 adapters were always extraordinarily rare, while the early years of Apple's transition to USB brought with it a raft of popular USB-to-ADB adapters. Apple's first mice used a DE-9 connection carrying quadrature signals; as the personal computer was still in its infancy with no standards, Apple's mice could be used on any system capable of using such a quadrature mouse, in combination with a spliced cable or adapter as necessary. The mouse created for the Apple Lisa was among the first commercial mice sold in the marketplace.
Included with the Lisa system in 1983, it was based on the mouse used in the 1970s on the Alto computer at Xerox PARC. Unique to this mouse was the use of a steel ball, instead of the usual rubber found in subsequent and modern mice, it connected to the computer by means of a standard unique squeeze-release connector. Though developed by Apple, it was designed by an outside firm, Hovey-Kelley, who built hundreds of prototypes and conducted exhaustive testing with focus groups in order to create the perfect device, their perseverance paid off as not only did they bring the design in on time and on budget, but the resulting device remained unchanged for 20 years. It was this mouse; every single aspect of the mouse was researched and developed, from how many buttons to include, to how loud the click should be. The original case design was Bill Dresselhaus's and took on an Art Deco flavor with its formal curving lines to coordinate with the Lisa; the Macintosh mouse was little changed from the original Lisa version and is interchangeable.
The case was a darker brown than Lisa's beige coloring and it
The Motorola 68030 is a 32-bit microprocessor in the Motorola 68000 family. It was released in 1987; the 68030 was the successor to the Motorola 68020, was followed by the Motorola 68040. In keeping with general Motorola naming, this CPU is referred to as the 030; the 68030 features 273,000 transistors with on-chip data caches of 256 bytes each. It has an on-chip memory management unit but does not have a built in floating-point unit; the 68881 and the faster 68882 floating point unit chips could be used with the 68030. A lower cost version of the 68030, the Motorola 68EC030, was released, lacking the on-chip MMU, it was available in both 132 pin QFP and 128 pin PGA packages. The poorer thermal characteristics of the QFP package limited the full 68030 QFP variant to 33 MHz. There was a small supply of QFP packaged EC variants; as a microarchitecture, the 68030 is a 68020 core with an additional 256 byte data cache and a process shrink and an added burst mode for the caches, where four longwords can be placed in the cache without further CPU intervention.
Motorola used the process shrink to pack more hardware on the die. The integration of the MMU made it more cost-effective than the 68020 with an external MMU. However, the 68030 can switch between asynchronous buses without a reset; the 68030 lacks some of the 68020's instructions, but it increases performance by ≈5% while reducing power draw by ≈25% compared to the 68020. The 68030 can be used with the 68020 bus, in which case its performance is similar to 68020 that it was derived from. However, the 68030 provides an additional synchronous bus interface which, if used, accelerates memory accesses up to 33% compared to an clocked 68020; the finer manufacturing process allowed Motorola to scale the full-version processor to 50 MHz. The EC variety topped out at 40 MHz; the 68030 was used in many models of the Apple Macintosh II and Commodore Amiga series of personal computers, NeXT Cube Alpha Microsystems multiuser systems, some descendants of the Atari ST line such as the Atari TT and the Atari Falcon.
It was used in Unix workstations such as the Sun Microsystems Sun-3x line of desktop workstations, laser printers and the Nortel Networks DMS-100 telephone central office switch. More the 68030 core has been adapted by Freescale into a microcontroller for embedded applications. LeCroy has used the 68EC030 in certain models of their 9300 Series digital oscilloscopes including “C” suffix models:87-88 and high performance 9300 Series models, along with the Mega Waveform Processing hardware option for 68020-based 9300 Series models; the 68EC030 is a low cost version of the 68030, the difference between the two being that the 68EC030 omits the on-chip memory management unit and is thus an upgraded 68020. The 68EC030 was used as the CPU for the low-cost model of the Amiga 4000, on a number of CPU accelerator cards for the Commodore Amiga line of computers, it was used in the Cisco Systems 2500 Series router, a small-to-medium enterprise computer internetworking appliance. The 50 MHz speed is exclusive to the plastic' 030 stopped at 40 MHz.
This article is based on material taken from the Free On-line Dictionary of Computing prior to 1 November 2008 and incorporated under the "relicensing" terms of the GFDL, version 1.3 or later. 68030 images and descriptions at cpu-collection.de Official information about the Freescale MC68030 microcontroller Motorola 68k family data sheets at bitsavers.org
The Macintosh Quadra is a family of personal computers designed and sold by Apple Computer, Inc. from October 1991 to October 1995. The Quadra, named for the Motorola 68040 central processing unit, replaced the Macintosh II family as the high-end Macintosh model; the first models were the Quadra 700 and Quadra 900, both introduced in October 1991. The Quadra 800, 840AV and 605 were added through 1993; the Macintosh Centris line was merged with the Quadra in October 1993, adding the 610, 650 and 660AV to the range. After the introduction of the Power Macintosh line in early 1994, Apple continued to produce and sell new Quadra models; the product manager for the Quadra family was Frank Casanova, the Product Manager for the Macintosh IIfx. The first computers bearing the Macintosh Quadra name were the Quadra 700 and Quadra 900, both introduced in 1991 with a central processing unit speed of 25 MHz; the 700 was a compact model using the same case dimensions as the Macintosh IIci, with a Processor Direct Slot expansion slot, while the latter was a newly designed tower case with five NuBus expansion slots and one PDS slot.
The 900 was replaced in 1992 with a CPU speed of 33 MHz. The line was joined by a number of "800-series" machines in a new minitower case design, starting with the Quadra 800, the "600-series" pizza box desktop cases with the Quadra 610. In 1993, the Quadra 840AV and 660AV were introduced at 25 MHz respectively, they included an AT&T Digital signal processor and S-Video and composite video input/output ports, as well as CD-quality microphone and audio output ports. The AV models introduced PlainTalk, consisting of the text-to-speech software MacinTalk Pro and speech control; however all of these features were poorly supported in software, DSP was not installed in AV Macs, which were based on the more-powerful PowerPC 601 CPU, powerful enough to handle the coprocessor's duties on its own. Apple hired marketing firm Lexicon Branding to come up with the name. Lexicon chose the name Quadra hoping to appeal to engineers by evoking technical terms like quadrant and quadriceps; the Quadra name was used for the successors to the Centris models that existed during 1993: The 610, the 650 and the 660AV.
Centris was a "mid-range" line of systems between the Quadra on the high end and the LC on the low end, but it was decided that there were too many product lines and the name was dropped. Some machines of this era including the Quadra 605 were sold as Performas; the last use of the name was for the Quadra 630, a variation of the LC 630 using a "full" Motorola 68040 instead of the LC's 68LC040, introduced together with it in 1994. The 630 was the first Mac to use an IDE based drive bus for the internal hard disk drive, whereas all earlier models had used SCSI; the first three Apple Workgroup Server models, the WGS 60, the WGS 80 and the WGS 95 were based on the Centris 610, the Quadra 800 and the Quadra 950, respectively. The transition to the Motorola 68040 was not as smooth as the previous transitions to the Motorola 68020 or Motorola 68030. Due to the Motorola 68040's split instruction and data caches, the Quadra had compatibility problems with self-modifying code. Apple fixed this by having the basic Mac OS memory copy call flush the caches.
This solved the vast majority of stability problems, but negated much of the Motorola 68040's performance improvements. Apple introduced a variant of the memory copy call that did not flush the cache; the new trap was defined in such a way that calling it on an older version of Mac OS would call the previous memory copy routine. The net effect of this was that many complex applications were slow or prone to crashing on the 68040, although developers adapted to the new architecture by relying on Apple's memory copy routines rather than their own, using the memory copy that did not flush the cache when appropriate. List of Macintosh models grouped by CPU type List of Macintosh models by case type Timeline of Macintosh models EveryMac.com - Macintosh Quadra series Lowendmac.com - Centris/Quadra Index