83-530: Control-Alt-Delete (often abbreviated to Ctrl+Alt+Del and sometimes called the "three-finger salute" or "Security Keys") is a computer keyboard command on IBM PC compatible computers, invoked by pressing the Delete key while holding the Control and Alt keys: Ctrl + Alt + Delete . The function of the key combination differs depending on the context but it generally interrupts or facilitates interrupting
166-464: A "'next generation' true 16-bit CPU", and with "More speed. More disk storage. More expansion" than the IBM PC or "other MS-DOS computers". While admitting in 1984 that many PC DOS programs did not work on the computer, the company stated that "the most popular, sophisticated software on the market" was available, either immediately or "over the next six months". Like IBM, Microsoft's apparent intention
249-535: A 32-bit operating system released during the 2000s can still operate many of the simpler programs written for the OS of the early 1980s without needing an emulator , though an emulator like DOSBox now has near-native functionality at full speed (and is necessary for certain games which may run too fast on modern processors). Additionally, many modern PCs can still run DOS directly, although special options such as USB legacy mode and SATA-to-PATA emulation may need to be set in
332-759: A commercial venture. Experience had shown that even if an operating system was technically superior to Windows, it would be a failure in the market ( BeOS and OS/2 for example). In 1989, Steve Jobs said of his new NeXT system, "It will either be the last new hardware platform to succeed, or the first to fail." Four years later in 1993, NeXT announced it was ending production of the NeXTcube and porting NeXTSTEP to Intel processors. Very early on in PC history, some companies introduced their own XT-compatible chipsets . For example, Chips and Technologies introduced their 82C100 XT Controller which integrated and replaced six of
415-491: A computer capable of running programs that are managed by MS-DOS". The main reason why an IBM standard is not worrying is that it can help competition to flourish. IBM will soon be as much a prisoner of its standards as its competitors are. Once enough IBM machines have been bought, IBM cannot make sudden changes in their basic design; what might be useful for shedding competitors would shake off even more customers. In February 1984 Byte wrote that "IBM's burgeoning influence in
498-558: A consumer PC manufacturer during April 2005, when it sold its laptop and desktop PC divisions ( ThinkPad / ThinkCentre ) to Lenovo for US$ 1.75 billion . As of October 2007, Hewlett-Packard and Dell had the largest shares of the PC market in North America. They were also successful overseas, with Acer , Lenovo , and Toshiba also notable. Worldwide, a huge number of PCs are " white box " systems assembled by myriad local systems builders. Despite advances of computer technology,
581-531: A few percentage points of market share was Apple Inc. 's Macintosh . The Mac started out billed as "the computer for the rest of us", but high prices and closed architecture drove the Macintosh into an education and desktop publishing niche, from which it only emerged in the mid-2000s. By the mid-1990s the Mac's market share had dwindled to around 5% and introducing a new rival operating system had become too risky
664-478: A function. For instance, in pre-boot environment (before an operating system starts) or in MS-DOS , Windows 3.0 and earlier versions of Windows or OS/2 , the key combination reboots the computer. Starting with Windows 95 , the key combination invokes a task manager or security related component that facilitates ending a Windows session or killing a frozen application. The soft reboot function via keyboard
747-505: A minor player with its own technology". The Economist predicted in 1983 that "IBM will soon be as much a prisoner of its standards as its competitors are", because "Once enough IBM machines have been bought, IBM cannot make sudden changes in their basic design; what might be useful for shedding competitors would shake off even more customers". After the Compaq Deskpro 386 became the first 80386-based PC, PC wrote that owners of
830-524: A proprietary operating system : "Who cares? If IBM does it, they will most likely just isolate themselves from the largest marketplace, in which they really can't compete anymore anyway". He predicted that in 1987 the market "will complete its transition from an IBM standard to an Intel/MS-DOS/expansion bus standard ... Folks aren't so much concerned about IBM compatibility as they are about Lotus 1-2-3 compatibility". By 1992, Macworld stated that because of clones, "IBM lost control of its own market and became
913-421: A range of machines from different vendors that had widely varying hardware. Those customers who needed other applications than the starter programs could reasonably expect publishers to offer their products for a variety of computers, on suitable media for each. Microsoft's competing OS was intended initially to operate on a similar varied spectrum of hardware, although all based on the 8086 processor. Thus, MS-DOS
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#1732798502365996-472: Is a shortcut for logging out. On Ubuntu Server , it is used to reboot a computer without logging in. Ctrl + Alt + Delete An equivalent function is Ctrl + NumLock (with Ctrl held down and pressing NumLock twice) As computers became ubiquitous, so too, has the jargon . Control-Alt-Delete can also mean "dump," or "do away with". The keystrokes are well known and infamous for escaping from problems in pop culture. For example, in
1079-416: Is a similar description that is more commonly used for modern computers. The designation "PC", as used in much of personal computer history , has not meant "personal computer" generally, but rather an x86 computer capable of running the same software that a contemporary IBM or Lenovo PC could. The term was initially in contrast to the variety of home computer systems available in the early 1980s, such as
1162-426: Is also known for his good-natured jab at Gates at the celebration of the 20th anniversary of the IBM PC on August 8, 2001 at The Tech Museum : "I have to share the credit. I may have invented it, but I think Bill made it famous." ; he quickly added it was a reference to Windows NT logon procedures ("Press Ctrl + Alt + Delete to log on"). During a question and answer presentation on 21 September 2013, Gates said "it
1245-689: Is an MDI text editor that opens all these files simultaneously, available in all versions of Windows beginning with Windows 3.0 , except Me and no longer after Windows 7. MSConfig is a front end interface application that allows the user to enable and disable drivers, Windows shell and applications separately from being loaded at startup by the aforementioned files and from the Run, RunEx, and RunOnce Windows Registry keys. SYSTEM.INI in Windows 3.x (3.0, 3.10 and Windows for Workgroups 3.11) and Windows 9x (95, 98 and Me): This Microsoft Windows article
1328-466: Is becoming a misnomer, as Intel has lost absolute control over the direction of x86 hardware development with AMD 's AMD64 . Additionally, non-Windows operating systems like macOS and Linux have established a presence on the x86 architecture. Although the IBM PC was designed for expandability, the designers could not anticipate the hardware developments of the 1980s, nor the size of the industry they would engender. To make things worse, IBM's choice of
1411-598: Is intercepted by the BIOS . The BIOS reacts by performing a soft reboot (also known as a warm reboot). Examples of such operating systems include DOS , Windows 3.0 in Standard Mode as well as earlier versions of Windows. In Windows 9x and Windows 3.0 running in 386 Enhanced mode, the keystroke combination is recognized by the Windows keyboard device driver . According to the value of the LocalReboot option in
1494-423: The [386Enh] section of system.ini , Windows performs one of several actions in response. If LocalReboot=On (default): If LocalReboot=Off , Windows performs a soft reboot. The Windows NT family of operating system, whose members do not have "NT" in their names since Windows 2000 , reserve Ctrl+Alt+Delete for the operating system itself. Winlogon , a core component of the operating system, responds to
1577-567: The Accelerated Graphics Port (AGP). Descendants of the x86 IBM PC compatibles, namely 64-bit computers based on " x86-64 /AMD64" chips comprise the majority of desktop computers on the market as of 2021, with the dominant operating system being Microsoft Windows . Interoperability with the bus structure and peripherals of the original PC architecture may be limited or non-existent. Many modern computers are unable to use old software or hardware that depends on portions of
1660-585: The Amiga , have been relegated to niche, enthusiast markets. In the past, the most successful exception was Apple 's Macintosh platform, which used non-Intel processors from its inception. Although Macintosh was initially based on the Motorola 68000 series , then transitioned to the PowerPC architecture, Macintosh computers transitioned to Intel processors beginning in 2006. Until 2020 Macintosh computers shared
1743-461: The Apple II , TRS-80 , and Commodore 64 . Later, the term was primarily used in contrast to Commodore 's Amiga and Apple 's Macintosh computers. These "clones" duplicated almost all the significant features of the original IBM PC architectures. This was facilitated by IBM's choice of commodity hardware components , which were cheap, and by various manufacturers' ability to reverse-engineer
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#17327985023651826-584: The BIOS firmware using a " clean room design " technique. Columbia Data Products built the first clone of the IBM personal computer , the MPC 1600 by a clean-room reverse-engineered implementation of its BIOS. Other rival companies, Corona Data Systems , Eagle Computer , and the Handwell Corporation were threatened with legal action by IBM, who settled with them. Soon after in 1982, Compaq released
1909-464: The Billy Talent song " Perfect World ", part of the lyrics include the sequence and associate it with resetting their memory and escaping from a situation: "Control-Alt-Deleted. Reset my memory." IBM PC compatible " IBM PC–compatible " refers to a class of computers that are technically compatible with the 1981 IBM PC and subsequent XT and AT models from computer giant IBM . Like
1992-665: The Compaq Portable . The Compaq was the first sewing machine-sized portable computer that was essentially 100% PC-compatible. The court decision in Apple v. Franklin , was that BIOS code was protected by copyright law, but it could reverse-engineer the IBM BIOS and then write its own BIOS using clean room design . Note this was over a year after Compaq released the Portable. The money and research put into reverse-engineering
2075-626: The IBM PS/2 computer that overcame many of the technical limits of the XT/AT bus, but this was rarely used as the basis for IBM-compatible computers since it required license payments to IBM both for the PS/2 bus and any prior AT-bus designs produced by the company seeking a license. This was unpopular with hardware manufacturers and several competing bus standards were developed by consortiums, with more agreeable license terms. Various attempts to standardize
2158-533: The Intel 8088 for the CPU introduced several limitations for developing software for the PC compatible platform. For example, the 8088 processor only had a 20-bit memory addressing space . To expand PC s beyond one megabyte, Lotus, Intel, and Microsoft jointly created expanded memory (EMS), a bank-switching scheme to allow more memory provided by add-in hardware, and accessed by a set of four 16- kilobyte "windows" inside
2241-631: The Macintosh computers offered by Apple Inc. and used mainly for desktop publishing at the time, the aging 8-bit Commodore 64 which was selling for $ 150 by this time and became the world's bestselling computer, the 32-bit Commodore Amiga line used for television and video production and the 32-bit Atari ST used by the music industry. However, IBM itself lost the main role in the market for IBM PC compatibles by 1990. A few events in retrospect are important: Despite popularity of its ThinkPad set of laptop PC's, IBM finally relinquished its role as
2324-507: The Macintosh had kept significant market share without having compatibility with the IBM PC, although that changed during the Intel Macs era running Mac OS X , often dual-booting Windows with Boot Camp . IBM decided in 1980 to market a low-cost single-user computer as quickly as possible. On August 12, 1981, the first IBM PC went on sale. There were three operating systems (OS) available for it. The least expensive and most popular
2407-558: The Multimedia PC (MPC) standard was set during 1990. A PC that met the minimum MPC standard could be marketed with the MPC logo, giving consumers an easy-to-understand specification to look for. Software that could operate on the most minimally MPC-compliant PC would be guaranteed to operate on any MPC. The MPC level 2 and MPC level 3 standards were set later, but the term "MPC compliant" never became popular. After MPC level 3 during 1996, no further MPC standards were established. By
2490-528: The 20-bit addressing. Later, Intel CPUs had larger address spaces and could directly address 16 MB (80286) or more, causing Microsoft to develop extended memory (XMS) which did not require additional hardware. "Expanded" and "extended" memory have incompatible interfaces, so anyone writing software that used more than one megabyte had to provide for both systems for the greatest compatibility until MS-DOS began including EMM386, which simulated EMS memory using XMS memory. A protected mode OS can also be written for
2573-432: The 80286, but DOS application compatibility was more difficult than expected, not only because most DOS applications accessed the hardware directly, bypassing BIOS routines intended to ensure compatibility, but also that most BIOS requests were made by the first 32 interrupt vectors, which were marked as "reserved" for protected mode processor exceptions by Intel. Video cards suffered from their own incompatibilities. There
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2656-583: The BIOS setup utility. Computers using the UEFI might need to be set at legacy BIOS mode to be able to boot DOS. However, the BIOS/UEFI options in most mass-produced consumer-grade computers are very limited and cannot be configured to truly handle OSes such as the original variants of DOS. The spread of the x86-64 architecture has further distanced current computers' and operating systems' internal similarity with
2739-459: The BIOS was a calculated risk. At the same time, many manufacturers such as Tandy / RadioShack , Xerox , Hewlett-Packard , Digital Equipment Corporation , Sanyo , Texas Instruments , Tulip , Wang and Olivetti introduced personal computers that supported MS-DOS, but were not completely software- or hardware-compatible with the IBM PC. Tandy described the Tandy 2000 , for example, as having
2822-525: The Force Quit panel. Control + ⌘ Command + Power restarts the computer. The original Mac OS X Server had an Easter egg in which pressing Control + ⌥ Option + Delete (as the Option key is the equivalent of Alt key on a Mac keyboard) would show an alert saying "This is not DOS!". On some Linux -based operating systems including Ubuntu and Debian , Control + Alt + Delete
2905-419: The IBM PC compatible architecture which are missing or do not have equivalents in modern computers. For example, computers which boot using Unified Extensible Firmware Interface -based firmware that lack a Compatibility Support Module, or CSM, required to emulate the old BIOS-based firmware interface, or have their CSMs disabled, cannot natively run MS-DOS since MS-DOS depends on a BIOS interface to boot. Only
2988-454: The IBM PC compatibles remained very much compatible with the original IBM PC computers, although most of the components implement the compatibility in special backward compatibility modes used only during a system boot . It was often more practical to run old software on a modern system using an emulator rather than relying on these features. In 2014 Lenovo acquired IBM's x86-based server ( System x ) business for US$ 2.1 billion . One of
3071-651: The IBM PC compatibles: try the package you want to use before you buy the computer." Companies modified their computers' BIOS to work with newly discovered incompatible applications, and reviewers and users developed stress tests to measure compatibility; by 1984 the ability to operate Lotus 1-2-3 and Flight Simulator became the standard, with compatibles specifically designed to run them. IBM believed that some companies such as Eagle, Corona, and Handwell infringed on its copyright, and after Apple Computer, Inc. v. Franklin Computer Corp. successfully forced
3154-489: The IBM PC's release. InfoWorld wrote on the first anniversary of the IBM PC that The dark side of an open system is its imitators. If the specs are clear enough for you to design peripherals, they are clear enough for you to design imitations. Apple ... has patents on two important components of its systems ... IBM, which reportedly has no special patents on the PC, is even more vulnerable. Numerous PC-compatible machines—the grapevine says 60 or more—have begun to appear in
3237-1268: The IBM PC. At first, few clones other than Compaq's offered truly full compatibility. Jerry Pournelle purchased an IBM PC in mid-1983, " rotten keyboard and all", because he had "four cubic feet of unevaluated software, much of which won't run on anything but an IBM PC. Although a lot of machines claim to be 100 percent IBM PC compatible, I've yet to have one arrive ... Alas, a lot of stuff doesn't run with Eagle, Z-100, Compupro , or anything else we have around here". Columbia Data Products's November 1983 sales brochure stated that during tests with retail-purchased computers in October 1983, its own and Compaq's products were compatible with all tested PC software, while Corona and Eagle's were less compatible. Columbia University reported in January 1984 that Kermit ran without modification on Compaq and Columbia Data Products clones, but not on those from Eagle or Seequa. Other MS-DOS computers also required custom code. By December 1983 Future Computing stated that companies like Compaq, Columbia Data Products, and Corona that emphasized IBM PC compatibility had been successful, while non-compatible computers had hurt
3320-432: The IBM PC. Many companies were reluctant to have their products' PC compatibility tested. When PC Magazine requested samples from computer manufacturers that claimed to produce compatibles for an April 1984 review, 14 of 31 declined. Corona specified that "Our systems run all software that conforms to IBM PC programming standards. And the most popular software does." When a BYTE journalist asked to test Peachtext at
3403-836: The INI files had begun to be phased out in favor of the Windows Registry . Windows NT 4.0 , 2000 , XP and Server 2003 still acknowledge some SYSTEM.INI entries in order to provide backwards compatibility with older 16-bit applications. Windows Vista and beyond also have SYSTEM.INI as well. However, when a fresh install of XP / Server 2003 is performed, the SYSTEM.INI file created contains by default only these lines: Microsoft bundles two specialized text/ ASCII editors for core configuration files (such as PROTOCOL.INI , WIN.INI , SYSTEM.INI , CONFIG.SYS , and AUTOEXEC.BAT ) with its operating systems. Sysedit
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3486-592: The OEM versions of MS-DOS were virtually identical, except perhaps for the provision of a few utility programs. MS-DOS provided adequate functionality for character-oriented applications such as those that could have been implemented on a text-only terminal . Had the bulk of commercially important software been of this nature, low-level hardware compatibility might not have mattered. However, in order to provide maximum performance and leverage hardware features (or work around hardware bugs), PC applications quickly developed beyond
3569-455: The PC community is stifling innovation because so many other companies are mimicking Big Blue", but The Economist stated in November 1983, "The main reason why an IBM standard is not worrying is that it can help competition to flourish". By 1983, IBM had about 25% of sales of personal computers between $ 1,000 and $ 10,000 , and computers with some PC compatibility were another 25%. As
3652-548: The Spring 1983 COMDEX , Corona representatives "hemmed and hawed a bit, but they finally led me ... off in the corner where no one would see it should it fail". The magazine reported that "Their hesitancy was unnecessary. The disk booted up without a problem". Zenith Data Systems was bolder, bragging that its Z-150 ran all applications people brought to test with at the 1984 West Coast Computer Faire . Creative Computing in 1985 stated, "we reiterate our standard line regarding
3735-472: The clone makers to stop using the BIOS. The Phoenix BIOS in 1984, however, and similar products such as AMI BIOS , permitted computer makers to legally build essentially 100%-compatible clones without having to reverse-engineer the PC BIOS themselves. A September 1985 InfoWorld chart listed seven compatibles with 256 KB RAM, two disk drives, and monochrome monitors for $ 1,495 to $ 2,320 , while
3818-423: The computer marketplace of the time. Until then Microsoft's business was based primarily on computer languages such as BASIC . The established small system operating software was CP/M from Digital Research which was in use both at the hobbyist level and by the more professional of those using microcomputers. To achieve such widespread use, and thus make the product viable economically, the OS had to operate across
3901-549: The dominant market player only to be virtually wiped out by Intel a year later. Intel has been the uncontested leader ever since. As the "Wintel" platform gained dominance Intel gradually abandoned the practice of licensing its technologies to other chipset makers; in 2010 Intel was involved in litigation related to their refusal to license their processor bus and related technologies to other companies like Nvidia . Companies such as AMD and Cyrix developed alternative x86 CPUs that were functionally compatible with Intel's. Towards
3984-584: The end of the 1990s, AMD was taking an increasing share of the CPU market for PCs. AMD even ended up playing a significant role in directing the development of the x86 platform when its Athlon line of processors continued to develop the classic x86 architecture as Intel deviated with its NetBurst architecture for the Pentium 4 CPUs and the IA-64 architecture for the Itanium set of server CPUs. AMD developed AMD64,
4067-472: The equivalent IBM PC cost $ 2,820 . The inexpensive Leading Edge Model D is even compatible with IBM proprietary diagnostic software, unlike the Compaq Portable. By 1986 Compute! stated that "clones are generally reliable and about 99 percent compatible", and a 1987 survey in the magazine of the clone industry did not mention software compatibility, stating that "PC by now has come to stand for
4150-649: The establishment of the Extended Industry Standard Architecture bus open standard by a consortium of IBM PC compatible vendors, redefining the 16-bit IBM AT bus as the Industry Standard Architecture (ISA) bus. Additional bus standards were subsequently adopted to improve compatibility between IBM PC compatibles, including the VESA Local Bus (VLB), Peripheral Component Interconnect (PCI), and
4233-620: The exception rather than the rule. Instead of placing importance on compatibility with the IBM PC, vendors began to emphasize compatibility with Windows . In 1993, a version of Windows NT was released that could operate on processors other than the x86 set. While it required that applications be recompiled, which most developers did not do, its hardware independence was used for Silicon Graphics (SGI) x86 workstations–thanks to NT's Hardware abstraction layer (HAL), they could operate NT (and its vast application library) . No mass-market personal computer hardware vendor dared to be incompatible with
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#17327985023654316-424: The first major extension not created by Intel, which Intel later adopted as x86-64 . During 2006 Intel began abandoning NetBurst with the release of their set of "Core" processors that represented a development of the earlier Pentium III. A major alternative to Wintel domination is the rise of alternative operating systems since the early 2000s, which marked as the start of the post-PC era . This would include both
4399-458: The hardware instead of making standard calls was faster, however; this was particularly relevant to games. Software addressing IBM PC hardware in this way would not run on MS-DOS machines with different hardware (for example, the PC-98 ). The IBM PC was sold in high enough volumes to justify writing software specifically for it, and this encouraged other manufacturers to produce machines that could use
4482-462: The hardware, for a variety of reasons: The first thing to think about when considering an IBM-compatible computer is, "How compatible is it?" In May 1983, Future Computing defined four levels of compatibility: During development, Compaq engineers found that Microsoft Flight Simulator would not run because of what subLOGIC 's Bruce Artwick described as "a bug in one of Intel's chips", forcing them to make their new computer bug compatible with
4565-496: The interfaces were made, but in practice, many of these attempts were either flawed or ignored. Even so, there were many expansion options, and despite the confusion of its users, the PC compatible design advanced much faster than other competing designs of the time, even if only because of its market dominance. During the 1990s, IBM's influence on PC architecture started to decline. "IBM PC compatible" becomes "Standard PC" in 1990s, and later " ACPI PC" in 2000s. An IBM-brand PC became
4648-510: The key combination in the following scenarios: In OS/2 , this keystroke combination is recognized by the OS/2 keyboard device driver, which notifies the session manager process. The normal session manager process in OS/2 versions 2.0 and later is the parent Workplace Shell process, which displays the "system is rebooting" window and triggers a soft reboot. If it is pressed twice in succession OS/2 triggers an immediate soft reboot, without waiting for
4731-668: The key combination to Ctrl + Alt + Del as a safety measure, a combination impossible to press with just one hand on the original IBM PC keyboard . The feature was originally conceived only as a development feature for internal use and not intended to be used by end users, as it triggered the reboot without warning or further confirmation—it was meant to be used by people writing programs or documentation so that they could reboot their computers without powering them down. Bill Gates (former Microsoft CEO ) remembered it as "just something we were using in development and it wouldn't be available elsewhere". The feature, however,
4814-471: The late 1990s, the success of Microsoft Windows had driven rival commercial operating systems into near-extinction, and had ensured that the "IBM PC compatible" computer was the dominant computing platform . This meant that if a developer made their software only for the Wintel platform, they would still be able to reach the vast majority of computer users. The only major competitor to Windows with more than
4897-428: The latest version of Windows, and Microsoft's annual WinHEC conferences provided a setting in which Microsoft could lobby for—and in some cases dictate—the pace and direction of the hardware of the PC industry. Microsoft and Intel had become so important to the ongoing development of PC hardware that industry writers began using the word Wintel to refer to the combined hardware-software system. This terminology itself
4980-487: The latter becoming the most popular. Because of the great number of third-party adapters and no standard for them, programming the PC could be difficult. Professional developers would operate a large test-suite of various known-to-be-popular hardware combinations. Meanwhile, consumers were overwhelmed by the competing, incompatible standards and many different combinations of hardware on offer. To give them some idea of what sort of PC they would need to operate their software,
5063-525: The market and competition grew IBM's influence diminished. In November 1985 PC Magazine stated "Now that it has created the [PC] market, the market doesn't necessarily need IBM for the machines. It may depend on IBM to set standards and to develop higher-performance machines, but IBM had better conform to existing standards so as to not hurt users". In January 1987, Bruce Webster wrote in Byte of rumors that IBM would introduce proprietary personal computers with
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#17327985023655146-540: The marketplace. By June 1983 PC Magazine defined "PC 'clone ' " as "a computer [that can] accommodate the user who takes a disk home from an IBM PC, walks across the room, and plugs it into the 'foreign' machine". Because of a shortage of IBM PCs that year, many customers purchased clones instead. Columbia Data Products produced the first computer more or less compatible with the IBM PC standard during June 1982, soon followed by Eagle Computer . Compaq announced its first product, an IBM PC compatible in November 1982,
5229-522: The new computer did not need to fear that future IBM products would be incompatible with the Compaq, because such changes would also affect millions of real IBM PCs: "In sticking it to the competition, IBM would be doing the same to its own people". After IBM announced the OS/2 -oriented PS/2 line in early 1987, sales of existing DOS-compatible PC compatibles rose, in part because the proprietary operating system
5312-542: The original IBM PC by introducing yet another processor mode with an instruction set modified for 64-bit addressing, but x86-64 capable processors also retain standard x86 compatibility. System.ini SYSTEM.INI is an initialization ( INI file) used in early versions of Microsoft Windows (from 1.01 up to Me ) to load device drivers and the default Windows shell ( Program Manager or Windows Explorer ), among other system settings. Many of these settings were honored in Windows 9x ( 95 , 98 and Me ), although
5395-514: The original IBM PC, they use an Intel x86 central processing unit and are capable of using interchangeable commodity hardware , such as expansion cards . Initially such computers were referred to as PC clones , IBM clones or IBM PC clones , but the term "IBM PC compatible" is now a historical description only, as the vast majority of microcomputers produced since the 1990s are IBM compatible. IBM itself no longer sells personal computers, having sold its division to Lenovo in 2005. " Wintel "
5478-521: The original XT circuits: one 8237 DMA controller, one 8253 interrupt timer, one 8255 parallel interface controller, one 8259 interrupt controller, one 8284 clock generator, and one 8288 bus controller. Similar non-Intel chipsets appeared for the AT-compatibles, for example OPTi's 82C206 or 82C495XLC which were found in many 486 and early Pentium systems. The x86 chipset market was very volatile though. In 1993, VLSI Technology had become
5561-509: The rapid growth of the smartphones (using Android or iOS) as an alternative to the personal computer; and the increasing prevalence of Linux and Unix-like operating systems in the server farms of large corporations such as Google or Amazon. The term "IBM PC compatible" is not commonly used presently because many current mainstream desktop and laptop computers are based on the PC architecture, and IBM no longer makes PCs. The competing hardware architectures have either been discontinued or, like
5644-542: The reputations of others like TI and DEC despite superior technology. At a San Francisco meeting it warned 200 attendees, from many American and foreign computer companies as well as IBM itself, to "Jump on the IBM PC-compatible bandwagon—quickly, and as compatibly as possible". Future Computing said in February 1984 that some computers were "press-release compatible", exaggerating their actual compatibility with
5727-539: The same effect, but this did not easily extend to the greater color depths and higher resolutions offered by SVGA adapters. An attempt at creating a standard named VESA BIOS Extensions (VBE) was made, but not all manufacturers used it. When the 386 was introduced, again a protected mode OS could be written for it. This time, DOS compatibility was much easier because of virtual 8086 mode . Unfortunately programs could not switch directly between them, so eventually, some new memory-model APIs were developed, VCPI and DPMI ,
5810-490: The same programs, expansion cards , and peripherals as the PC. The x86 computer marketplace rapidly excluded all machines which were not hardware-compatible or software-compatible with the PC. The 640 KB barrier on "conventional" system memory available to MS-DOS is a legacy of that period; other non-clone machines, while subject to a limit, could exceed 640 KB. Rumors of "lookalike," compatible computers, created without IBM's approval, began almost immediately after
5893-481: The same system architecture as their Wintel counterparts and could boot Microsoft Windows without a DOS Compatibility Card . However, with the transition to the internally developed ARM -based Apple silicon , they are again the exception to IBM compatibility. The processor speed and memory capacity of modern PCs are many orders of magnitude greater than they were for the original IBM PC and yet backwards compatibility has been largely maintained –
5976-502: The session manager process. In both cases, the system flushes the page cache , cleanly unmounts all disc volumes, but does not cleanly shut down any running programs (and thus does not save any unsaved documents, or the current arrangements of the objects on the Workplace Shell desktop or in any of its open folders). Ctrl+Alt+Delete is not a keyboard shortcut on macOS . Instead, ⌘ Command + ⌥ Option + Esc brings up
6059-484: The simple terminal applications that MS-DOS supported directly. Spreadsheets , WYSIWYG word processors , presentation software and remote communication software established new markets that exploited the PC's strengths, but required capabilities beyond what MS-DOS provided. Thus, from very early in the development of the MS-DOS software environment, many significant commercial software products were written directly to
6142-569: The strengths of the PC-compatible design is its modular hardware design. End-users could readily upgrade peripherals and, to some degree, processor and memory without modifying the computer's motherboard or replacing the whole computer, as was the case with many of the microcomputers of the time. However, as processor speed and memory width increased, the limits of the original XT/AT bus design were soon reached, particularly when driving graphics video cards. IBM did introduce an upgraded bus in
6225-463: The very successful Compaq Portable , also with a clean-room reverse-engineered BIOS, and also not challenged legally by IBM. Early IBM PC compatibles used the same computer buses as their IBM counterparts, switching from the 8-bit IBM PC and XT bus to the 16-bit IBM AT bus with the release of the AT. IBM's introduction of the proprietary Micro Channel architecture (MCA) in its PS/2 series resulted in
6308-566: Was PC DOS made by Microsoft . In a crucial concession, IBM's agreement allowed Microsoft to sell its own version, MS-DOS , for non-IBM computers. The only component of the original PC architecture exclusive to IBM was the BIOS (Basic Input/Output System). IBM at first asked developers to avoid writing software that addressed the computer's hardware directly and to instead make standard calls to BIOS functions that carried out hardware-dependent operations. This software would run on any machine using MS-DOS or PC DOS. Software that directly addressed
6391-432: Was a mistake", referring to the decision to use Ctrl+Alt+Del as the keyboard combination to log into Windows. Gates stated he would have preferred a single button to trigger the same actions, but could not get IBM to add the extra button into the keyboard layout. By default, when the operating system is running in real mode (or in a pre-boot environment, when no operating system is started yet), this keystroke combination
6474-491: Was detailed in IBM's technical reference documentation to the original PC and thereby revealed to the general public. Bradley viewed this work as just one small task out of many: "It was five minutes, 10 minutes of activity, and then I moved on to the next of the 100 things that needed to get done." In a March 2018 email, one of Bradley's co-workers confirmed the command was invented in 1981 in Boca Raton , Florida. Bradley
6557-438: Was for several years sold only as an OEM product. There was no Microsoft-branded MS-DOS: MS-DOS could not be purchased directly from Microsoft, and each OEM release was packaged with the trade dress of the given PC vendor. Malfunctions were to be reported to the OEM, not to Microsoft. However, as machines that were compatible with IBM hardware—thus supporting direct calls to the hardware—became widespread, it soon became clear that
6640-477: Was no standard interface for using higher-resolution SVGA graphics modes supported by later video cards. Each manufacturer developed their own methods of accessing the screen memory, including different mode numberings and different bank switching arrangements. The latter were used to address large images within a single 64 KB segment of memory. Previously, the VGA standard had used planar video memory arrangements to
6723-465: Was not available. In 1988, Gartner Group estimated that the public purchased 1.5 clones for every IBM PC. By 1989 Compaq was so influential that industry executives spoke of "Compaq compatible", with observers stating that customers saw the company as IBM's equal or superior. After 1987, IBM PC compatibles dominated both the home and business markets of commodity computers, with other notable alternative architectures being used in niche markets, like
6806-468: Was originally designed by David Bradley . Bradley, as the chief engineer of the IBM PC project and developer of the machine's ROM-BIOS , had originally used Ctrl + Alt + Esc , but found it was too easy to bump the left side of the keyboard and reboot the computer accidentally. According to his own account, Mel Hallerman, who was the chief programmer of the project, therefore suggested switching
6889-467: Was that application writers would write to the application programming interfaces in MS-DOS or the firmware BIOS, and that this would form what would now be termed a hardware abstraction layer . Each computer would have its own Original Equipment Manufacturer (OEM) version of MS-DOS, customized to its hardware. Any software written for MS-DOS would operate on any MS-DOS computer, despite variations in hardware design. This expectation seemed reasonable in
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