Influence of the IBM PC on the personal computer market

In 1984, Phoenix Technologies began licensing its clone of the IBM PC BIOS. The Phoenix BIOS and competitors such as AMI BIOS made it possible for anyone to market a PC compatible computer,[26][27] without having to develop a compatible BIOS like Compaq.

Although based on the i8086 and enabling the creation of relatively low-cost x86-based systems, the Intel 80186 quickly lost appeal for x86-based PC builders because the supporting circuitry inside the Intel 80186 chip was incompatible with those used in the standard PC chipset as implemented by IBM. It was very rarely used in personal computers after 1982.

Imagine that Cray computer decides to make a personal computer. It has a 100 MHz processor, 20 megabytes of RAM, 500 megabytes of disk storage, a screen resolution of 1024 X 1024 pixels, relies entirely on voice recognition for input, fits in your shirt pocket and costs $3,000. What's the first question that the computer community asks? "Is it PC compatible?"

— InfoWorld, February 1984[28]

You don't ask whether a new machine is fast or slow, new technology or old. The first question is, "Is it PC compatible?"

— Creative Computing, November 1984[17]

In February 1984 BYTE described how "the personal computer market seems to be shadowed under a cloud of compatibility: the drive to be compatible with the IBM Personal Computer family has assumed near-fetish proportions", which it stated was "inevitable in the light of the phenomenal market acceptance of the IBM PC".[29] The magazine cited the announcement by North Star in fall 1983 of its first PC-compatible microcomputer. Founded in 1976, North Star had long been successful with 8-bit S-100 bus products, and had introduced proprietary 16-bit products, but now the company acknowledged that the IBM PC had become a "standard", one which North Star needed to follow. BYTE described the announcement as representative of the great impact IBM had made on the industry:[30]

It's become painfully obvious that the key to survival as a major manufacturer is acceptance by the business community. The IBM PC has unquestionably opened the door to that market wider than any personal computer before it, but in so doing has made compatibility a primary factor in microcomputer design, for better or for worse. Recent announcements by North Star ... and a host of smaller firms seem to indicate that the 8088/MS-DOS/IBM-compatible bandwagon is becoming much more like a speeding freight train.

The magazine expressed concern that "IBM's burgeoning influence in the PC community is stifling innovation because so many other companies are mimicking Big Blue".[29] Admitting that "it's what our dealers asked for", Kaypro also introduced the company's first IBM compatible that year.[31] Tandy—which had once had as much as 60% of the personal-computer market, but had attempted to keep technical information secret to monopolize software and peripheral sales[32]—also began selling non-proprietary computers;[33] four years after its Jon Shirley predicted to InfoWorld that the new IBM PC's "major market would be IBM addicts",[34] the magazine in 1985 similarly called the IBM compatibility of the Tandy 1000 "no small concession to Big Blue's dominating stranglehold" by a company that had been "struggling openly in the blood-soaked arena of personal computers".[35] The 1000 was compatible with the PC but not compatible with its own Tandy 2000 MS-DOS computer.[36][37] IBM's mainframe rivals, the BUNCH, introduced their own compatibles,[38] and when Hewlett-Packard introduced the Vectra InfoWorld stated that the company was "responding to demands from its customers for full IBM PC compatibility".[39]

I believe that the era when a machine could be introduced successfully into the marketplace with a total dearth of software ended abruptly with the Macintosh. And those days will not return.

— Creative Computing, February 1985[40]

Mitch Kapor of Lotus Development Corporation said in 1984 that "either you have to be PC-compatible or very special".[41] "Compatibility has proven to be the only safe path", Microsoft executive Jim Harris stated in 1985,[42] while InfoWorld wrote that IBM's competitors were "whipped into conformity" with its designs, because of "the total failure of every company that tried to improve on the IBM PC".[43] Customers only wanted to run PC applications like 1-2-3, and developers only cared about the massive PC installed base, so any non-compatible—no matter its technical superiority—from a company other than Apple failed for lack of customers and software.[28] Compatibility became so important that Dave Winer joked that year (referring to the PC AT's incomplete compatibility with the IBM PC), "The only company that can introduce a machine that isn't PC compatible and survive is IBM".[42]

By 1985, the shortage of IBM PCs had ended, causing financial difficulties for many vendors of compatibles; nonetheless, Harris said, "The only ones that have done worse than the compatibles are the noncompatibles".[42] The PC standard was similarly dominant in Europe, with Honeywell Bull, Olivetti, and Ericsson selling compatibles and software companies focusing on PC products.[44] By the end of the year PC Magazine stated that even IBM could no longer introduce a rumored proprietary, non-compatible operating system. Noting that the company's unsuccessful PCjr's "cardinal sin was that it wasn't PC compatible", the magazine wrote that "backward compatibility [with the IBM PC] is the single largest concern of hardware and software developers. The user community is too large and demanding to accept radical changes or abandon solutions that have worked in the past."[45]

Within a few years of the introduction of fully compatible PC clones, almost all rival business personal computer systems, and alternate x86 using architectures, were gone from the market. Despite the inherent dangers of an industry based on a de facto "standard",[46] a thriving PC clone industry emerged. The only other non-IBM PC-compatible systems that remained were those systems that were classified as home computers, such as the Apple II series, or business systems that offered features not available on the IBM PC, such as a high level of integration (e.g., bundled accounting and inventory) or fault-tolerance and multitasking and multi-user features.

Internal view of a PC compatible computer, showing components and layout.

Compaq's prices were comparable to IBM's, and the company emphasized its PC compatibles' features and quality to corporate customers. From mid-1985, what Compute! described as a "wave" of inexpensive clones from American and Asian companies caused prices to decline; by the end of 1986, the equivalent to a $1600 real IBM PC with 256K RAM and two disk drives cost as little as $600, lower than the price of the Apple IIc. Consumers began purchasing DOS computers for the home in large numbers; Tandy estimated that half of its 1000 sales went to homes, the new Leading Edge Model D comprised 1% of the US home-computer market that year, and toy and discount stores sold a clone made by Hyundai like a stereo, without a demonstrator model or salesman.[47][48][49][50][51][52]

Tandy and other inexpensive clones succeeded with consumers—who saw them as superior to lower-end game machines—where IBM failed two years earlier with the PCjr. They were as inexpensive as home computers of a few years earlier, and comparable in price to the Commodore Amiga, Atari ST, and Apple IIGS. Unlike the PCjr, clones were as fast as or faster than the IBM PC and highly compatible so users could bring work home; the large DOS software library reassured those worried about orphaned technology. Consumers used them for both spreadsheets and entertainment, with the former ability justifying buying a computer that could also perform the latter.[49][50][51][48] PCs and compatibles also gained a significant share of the educational market, while longtime leader Apple lost share.[53]

At the January 1987 Consumer Electronics Show, both Commodore and Atari announced their own clones.[54] By 1987 the PC industry was growing so quickly that the formerly business-only platform had become the largest and most important market for computer game companies, outselling games for the Apple II or Commodore 64. With the EGA video card, an inexpensive clone was better for games than the other computers.[55][56][57] MS-DOS software was 77% of all personal computer software sold by dollar value in the third quarter of 1988, up 47% year over year.[58] By 1989 80% of readers of Compute! owned DOS computers,[59] and the magazine announced "greater emphasis on MS-DOS home computing".[60]

IBM's influence on the industry decreased, as competition increased and rivals introduced computers that improved on IBM's designs while maintaining compatibility. In 1986 the Compaq Deskpro 386 was the first computer based on the Intel 80386. In 1987 IBM unsuccessfully attempted to regain leadership of the market with the Personal System/2 line and proprietary MicroChannel Architecture.

By 1990, Computer Gaming World told a reader complaining about the many reviews of PC games that "most companies are attempting to get their MS-DOS products out the door, first".[61] It reported that MS-DOS comprised 65% of the computer-game market, with the Amiga at 10%; all other computers, including the Macintosh, were below 10% and declining.[62] The Amiga and most others, such as the ST and various MSX2 computers, remained on the market until PC compatibles gained sufficient multimedia capabilities to compete with home computers. With the advent of inexpensive versions of the VGA video card and the Sound Blaster sound card (and its clones), most of the remaining home computers were driven from the market.

By 1995, other than the Macintosh, almost no new consumer-oriented systems were sold that were not IBM PC clones. The Macintosh originally used Motorola's 68000 family of processors, later migrating to the PowerPC architecture. Throughout the 1990s Apple would steadily transition the Macintosh platform from proprietary expansion interfaces to use standards from the PC world such as IDE, PCI and USB. In 2006, Apple converted the Macintosh to the Intel x86 architecture. Modern Macintosh computers are essentially IBM PC compatibles, capable of booting Microsoft Windows and running most IBM PC-compatible software, but still retain unique design elements that support Apple's Mac OS X operating system.

In 2008, Sid Meier listed the IBM PC as one of the three most important innovations in the history of video games.[63]

Early after the launch of the IBM PC in 1981, there were still dozens of systems that were not IBM PC-compatible, but did use Intel x86 chips.[64] They used Intel 8088, 8086, or 80186 processors, and almost without exception offered an OEM version of MS-DOS (as opposed to the OEM version customized for IBM's use). However, they generally made no attempt to copy the IBM PC's architecture, so these machines had different I/O addresses, a different system bus, different video controllers, and other differences from the original IBM PC. These differences, which were sometimes rather minor, were used to improve upon the IBM PC's design, but as a result of the differences, software that directly manipulated the hardware would not run correctly. In most cases, the x86-based systems that didn't use a fully IBM PC compatible design didn't sell well enough to attract support from software manufacturers, though a few computer manufacturers arranged for compatible versions of popular applications to be developed and sold specifically for their machines.

Fully IBM PC-compatible clones appeared on the market shortly thereafter, as the advantages of cloning became impossible to ignore. But before that some of the more notable systems that were x86-compatible, but not real clones, were:

• the ACT Apricot by ACT
• the Dulmont Magnum
• the Epson QX-16
• the Seequa Chameleon
• the HP-150 by Hewlett-Packard and the later HP 95LX, HP 100LX, HP 200LX, HP 1000CX, HP OmniGo 700LX, HP OmniGo 100, and HP OmniGo 120.
• the Hyperion by Infotech Cie used its own H-DOS OEM version of MS-DOS and was, for a time, to be manufactured by Commodore as its first PC compatible.
• the MBC-550 by Sanyo had many differences, including non-interchangeability of diskettes and non-standard ROM location.
• the DG-One by Data General was an early laptop with full 80x25 LCD screen that could boot some generic DOSes but worked best with their OEM version of MS-DOS, and had some hardware incompatibilities (especially in the serial I-O chip) as part of the compromise to reduce power consumption. Later models were more compatible with generic PC clones.
• the DG/10 by Data General had two processors, one an Intel 8086, running a very-modified[65] version of MSDOS (alternatively: CP/M-86) in a patented closely coupled arrangement with Data General's own microECLIPSE (the 8086 "invisibly" calling the microECLIPSE whenever it needed access to some peripherals, such as disks, while the 8086 had control over other peripherals such as the screen).
• the 80186-based Mindset graphics computer
• the Morrow Designs' Morrow Pivot[66]
• the MZ-5500 by Sharp
• the Decision Mate V from NCR Corporation;[67][68] its version of MS-DOS was called NCR-DOS
• the MikroMikko_2 by Nokia
• the NorthStar Advantage
• the PC-9801 systems from NEC[69]
• the Rainbow 100 from DEC
• the RM Nimbus by RM plc
• the Tandy 2000 by RadioShack
• the Texas Instruments TI Professional[70]
• the Torch Graduate by Torch Computers
• the Tulip System-1 by Tulip
• the Victor 9000 by Sirius Systems Technology
• the :YES by Philips was late on the market, ran DOS Plus and MS-DOS, but by using an 80186 it was incompatible with IBM's PC
• the Z-100 by Zenith with an MS-DOS OEM version named Z-DOS

Not all manufacturers immediately switched to the Intel x86 microprocessor family and MS-DOS. A few companies continued releasing systems based on non-Intel architectures.[71]

Some of these systems used a 32-bit microprocessor, the most popular being the Motorola 68000. Others continued to use 8-bit microprocessors. Many of these systems were eventually forced out of the market by the onslaught of the IBM PC clones, although their architectures may have had superior capabilities, especially in the area of multimedia. The PC architectures of that era often only had a CGA display, and no other sound system than the internal PC speaker.

Three systems of this era, while now extinct, have thriving legacies:

• The Apple Lisa by Apple Inc. was the predecessor of the Apple Macintosh, inspiring the Macintosh's design. The original Macintosh used a Motorola 68000 chip like the Lisa, and had a sufficiently similar design that some Lisa systems were converted for sale as "Macintosh XL" computers.
• The Acorn Computers Acorn Archimedes, later named the Risc PC, used a custom-designed microprocessor: the ARM. The ARM architecture continues to be popular, appearing in nearly all mobile phones and in many hand-held devices like Apple's iPhone, iPod and iPad, as well as small UNIX-based systems. The Risc PC's descendants include the A9home, the Iyonix PC and the RiscStation R7500.[72]
• The Sun Microsystems Sun-1[73] and Sun-2 families of BSD UNIX systems introduced the SunOS UNIX operating system, running on Motorola 680x0 chips. Sun's current large-scale UNIX systems use the SPARC processor family developed by Sun, but run a descendant of System V called Solaris.

• the 8-bit Commodore PET and CBM series
• the 8-bit Atari 800 and successors
• the Cromemco CS-1
• Intertec's Compustar II VPU Model 20[74]
• the Corvus Concept
• the Kaypro 10
• the Fujitsu Micro 16s[75]
• the Micro Decision by Morrow Designs[76]
• the MTU-130 by Micro Technology Unlimited[77]
• the Xerox 820
• the Epson QX-10
• the RoadRunner from MicroOffice[78]
• the TRS-80 Model II by Tandy/Radio Shack
  • the following year the TRS-80 Model 12 and TRS-80 models 16 and 16e
    • still later the Tandy 6000
• the TRS-80 Model III by Tandy/Radio Shack
  • in April 1983, the TRS-80 Model 4 and TRS-80 Model 4P