| Windows NT 3.1 | |
|---|---|
| Version of theWindows NT operating system | |
 | |
 Screenshot of Windows NT 3.1 | |
| Developer | Microsoft |
| OS family | Microsoft Windows |
| Source model | Closed-source |
| Released to manufacturing | July 27, 1993; 32 years ago (1993-07-27)[1] |
| Latest release | Service Pack 3 (3.1.528) / October 29, 1994; 31 years ago (1994-10-29) |
| Supported platforms | IA-32,Alpha,MIPS |
| Kernel type | Hybrid (NT) |
| Userland | |
| License | Commercial software |
| Preceded by | Windows 3.1 (1992) |
| Succeeded by | Windows NT 3.5 (1994) |
| Support status | |
| Unsupported as of December 31, 2000[2] | |
Windows NT 3.1 is the first major release of theWindows NToperating system developed byMicrosoft, released on July 27, 1993. It marked the company's entry into the corporate computing environment, designed to support largenetworks and to be portable, compiled forIntel x86,DEC Alpha andMIPS basedworkstations andservers.[3] It was Microsoft's first32-bit operating system, providing advantages over the constrictive16-bit architecture of previous versions of Windows that relied onDOS, but retaining adesktop environment familiar toWindows 3.1 users.[3]
Windows NT began as a rewrite of theOS/2 operating system, which Microsoft had co-developed withIBM but failed to gain much traction againstUnix, with vendorSun Microsystems dominating the market for powerful desktop workstations.[4] For several reasons, including the market success ofWindows 3.0 in 1990, Microsoft decided to advance Windows rather than OS/2 and relinquished their OS/2 development responsibilities. Byextending the Windows brand and beginning NT atversion 3.1, like Windows 3.1 which had establishedbrand recognition andmarket share, Microsoft implied that consumers should expect a familiaruser experience. The nameWindows NT ("New Technology") advertised that this was a re-engineered version of Windows.
First publicly demonstrated atComdex 1991, NT 3.1 was released in 1993 in two editions: Workstation and Advanced Server. When Windows NT premiered, their sales were limited by highsystem requirements, and a general lack of 32-bitapplications to take advantage of the OS's data processing capabilities. It sold about 300,000 copies before it was succeeded byWindows NT 3.5 in 1994. On December 31, 2000, Microsoft declared Windows NT 3.1 obsolete and stopped providing support and updates for the system.
Windows NT 3.1 was the first version of Windows to use 32-bit flat virtual memory addressing on 32-bit processors. Its companion product, Windows 3.1, used segmented addressing and switches from 16-bit to 32-bit addressing in pages.
The origins of Windows NT date back to 1988,[5] where Microsoft had a major foothold on thepersonal computer market due to the use of itsMS-DOS as the operating system ofIBM PC compatibles.Nathan Myhrvold, who had joined Microsoft after its acquisition of Dynamical Systems Research, identified two major threats to Microsoft's monopoly—RISC architectures, which proved to be more powerful than the equivalentIntel processors that MS-DOS ran on, andUnix, a family ofcross-platformmultitasking operating systems with support formultiprocessing andnetworking.[6]: 34 While the widespread use of Unix was hindered by the need to adapt programs for each individual variant,Bill Gates believed that the combination of a Unix-like operating system with RISC processors could be a market threat, prompting the need for Microsoft to develop a "Unix killer" that could run on multiple architectures.[6]: 35 Myhrvold wanted to develop a new system that would run on RISC workstations andIntelchips andmultiprocessing computers.[5] Gates had also hiredDave Cutler fromDigital Equipment Corporation to assist in developing the new operating system; Cutler left DEC after the cancellation of thePRISM architecture and itsMICA operating system, and agreed to join Microsoft on the condition that he be able to bring a number of staff members from his team at DEC with him.[5][6]: 17–37 Cutler arrived at Microsoft in October 1988, and began working on the development of the operating system in November.[6]: 38 [7]
The operating system was first developed as a revised version ofOS/2, an operating system Microsoft had jointly developed withIBM.[8]: 43–44 While OS/2 was originally intended to succeed MS-DOS, it had yet to be commercially successful. The OS was to be designed so it could beported to different processor platforms, and support multiprocessor systems, which few operating systems did at that time.[6]: 33 [8]: 2 [9] To target the enterprise market, the OS was also to support networking, thePOSIX standard, and a security platform compliant with the "Orange Book" standards; which would require the OS to be amulti-user system with a permission framework and the ability to audit security-related events.[10]
Both Microsoft and IBM wanted to market an operating system that appealed to corporate "enterprise software" customers. That meant greatersecurity,reliability, processing power, andcomputer networking features. However, since Microsoft also wanted to capture market share from Unix on othercomputing platforms, they needed asystem design that was moreportable than that of OS/2.
To this end, Microsoft began by developing and testing their new operating system for a non-x86 processor: anemulated version of theIntel i860. Alluding to the chip's codename, "N10", Microsoft codenamed their operating systemNT OS/2.[11] DEC preemptively sued Microsoft, alleging that they stole code from MICA for use in the new operating system. In an out-of-court settlement, Microsoft agreed to make NT OS/2 compatible with DEC'sAlpha processor.[7]
The development team originally estimated that development would be complete within 18 months. By April 1989, the NT OS/2 kernel could run inside the i860 emulator. However, the development team later determined that the i860 was unsuitable for the project. By December they had begun porting NT OS/2 to theMIPSR3000 processor instead, and completed the task in three months.[11] Senior Microsoft executivePaul Maritz was targeting a release date in 1992, but the development schedule was uncertain. The company was eager to silence naysayers who speculated that NT wouldn't be on the market until 1994, and had planned to present the new OS atCOMDEX in 1990.[8]: 84–85
In May 1990, Microsoft releasedWindows 3.0, a new version of its MS-DOS-basedWindowsdesktop environment. Windows 3.0 sold well, and the resulting shift in Microsoft's marketing strategy eroded their partnership with IBM—who wanted Microsoft to concentrate solely on developing OS/2 as its primary platform as opposed to building their future business around Windows.[6]: 100 Users and developers were unsure of whether to adopt Windows or OS/2 due to these uncertainties (a situation magnified by the fact that the operating systems were incompatible with each other at theAPI level), while Microsoft's resources were also being drained by the simultaneous development of multiple operating systems.[8]: 98–99 [12] In August 1990, as a response to the popularity of Windows 3.0, the NT OS/2 team decided to re-work the operating system to use an extended32-bit port of theWindows API known as Win32. Win32 maintained the familiar structure of the16-bit APIs used by Windows, which would allow developers to easily adapt their software for the new platform while maintaining a level of compatibility with existing software for Windows.[13] With the shift to a Windows-like architecture, the operating system'sshell was also changed from OS/2'sPresentation Manager to Windows'Program Manager.[6]: 102–105
Due to these changes, NT was not presented at COMDEX 1990 as was originally planned.[6]: 102 Neither the general public nor IBM knew about the transformation of NT OS/2 intoWindows NT at the time.[6]: 108 Although the companies did agree to a revised partnership where IBM and Microsoft would alternate developing major versions of OS/2 instead of collaborating on each version,[14] IBM eventually learned of Microsoft's Windows NT plans in January 1991, and immediately ended the OS/2 partnership. IBM would solely develop OS/2 2.0 (as was planned under the amended version) and all future versions, without any further involvement from Microsoft.[8]: 108–109 [13]
In October 1991, Windows NT received its first public demonstration at COMDEX. In an effort to ensure software taking advantage of Windows NT was available upon its release (scheduled for late-1992), Microsoft also distributed a 32-bitsoftware development kit to selected developers in attendance.[6]: 165 [15] The demonstration was positively received;PC Magazine called Windows NT "the modern reinvention of the operating system", but at the same time claimed that it was unlikely that the promisedbackward compatibility would be kept for the final release.[8]: 175–176 [16] In March 1992, Microsoft also releasedWin32s, which would allowWindows 3.1 to have partial compatibility with Windows NT programs for the purposes of developing software optimized for the platform.[17]
At Microsoft'sWin32 Professional Developers Conference in June 1992, Windows NT was demonstrated running on x86 and MIPS processors, while a beta version of Windows NT and an updated development kit were also made available.[18] Concurrently, Microsoft announced a new version of itsSQL Server product for Windows NT; Unix vendors feared that the software could be akiller app that would affect the market share of Unix systems.[19][20] Concerns were also raised over NT's memory usage; while most computers of the era shipped with 4 megabytes ofRAM, 16 MB was recommended for NTs. Due to the high cost of RAM at the time, critics thought that its high system requirements could affect the sales and adoption of Windows NT. Steps were taken to reduce its memory usage through methods such aspaging.[8]: 227–249
Microsoft began releasing public beta builds of NT in October 1992, and a month later at COMDEX, a presentation focusing on third-party software for Windows NT was held.[21][22][23] The final pre-release version of NT was released in March 1993, alongside the unveiling of the server version,LAN Manager for Windows NT. Although its stability and performance had improved, there were still fears that the OS could be released in an unfinished state or delayed further into 1993.[24][25]
Byextending the Windows brand and beginning NT atversion 3.1, likeWindows 3.1 which had establishedbrand recognition andmarket share, Microsoft implied that consumers should expect a familiaruser experience yet re-engineered.
Windows NT 3.1 and Windows NT 3.1 Advanced Server (so numbered to associate them withWindows 3.1) were released on July 26, 1993.[6]: 300 At first, only the x86 and MIPS versions shipped; the DEC Alpha version followed in September.[11][26] Microsoft sold the workstation version for$495, and the server version for$1,495. Ostensibly, the server price was meant to be a promotional discount offered only during the first six months of sale, but they never raised the retail price to the listed one—$2,995.[27][28] 250 programmers[29] wrote 5.6 millionlines of code;[6]: 290 the development cost$150 million.[6]: 307 In the last year of development, the team fixed more than 30,000 bugs.[6]: 300
During the product's lifecycle, Microsoft published threeservice packs: Service Pack 1 was released on October 8, 1993; Service Pack 2 followed on January 24, 1994; and Service Pack 3's release date was October 29, 1994. The service packs were distributed on CD-ROM and floppy disk, and also throughbulletin board systems,CompuServe, and theInternet. Microsoft terminated support for the operating system on December 31, 2000. Support for Windows NT 3.1 RTM (without a service pack) ended on January 8, 1994. Service Pack 1 support ended on April 24, 1994, and finally, Service Pack 2 support ended on January 29, 1995, only 1 year after general availability.
Windows NT 3.1 was localized into various languages. Besides English, it was available in Dutch, French, German, Japanese, Spanish and Swedish. The version for workstations, but not Windows NT 3.1 Server, was additionally available in Danish, Finnish, Italian, Norwegian and Portuguese.[30]
Cutler set three main goals for Windows NT. The first goal was portability: in contrast to previous operating systems, which were strongly tied to one architecture, Windows NT should be able to operate on multiple architectures.[6]: 53 To meet this goal, most of the operating systems, including the operating system core, had to be written in theC programming language.[31] During the planning phase it was clear that this would cause Windows NT to have higher memory consumption than all previous operating systems.[6]: 55 Besides the graphics system and parts of the networking system, which were written inC++, only parts of the operating systems which required direct hardware access and performance critical functions were written inassembly language. These parts were isolated so that they could easily be rewritten when porting the operating system to a new architecture.[8]: 89
The second goal wasreliability: The system should no longer crash due to a faulty application or faulty hardware.[8]: 9 This way, the operating system should be made attractive for critical applications.[6]: 54 To meet this goal, the architecture of Windows NT was designed so that the operating system core was isolated and applications could not access it directly.[6]: 56 The kernel was designed as amicrokernel and components of the core were to run atop the kernel in a modular fashion; Cutler knew this principle from his work at Digital.[6]: 57 Reliability also includes security, and the operating system should be able to resist external attacks.[8]: 9 Mainframes already had a system where every user had their own account which was assigned specific rights by theadministrator, this way, users could be prevented access to confidential documents.[8]: 157–158 Avirtual memory management was designed to thwart attacks bymalware and prevent users from accessing foreign areas of memory.[8]: 10
The third goal was calledpersonality: The operating system should be able to run applications designed for various operating systems, such asWindows, MS-DOS and OS/2 applications.[6]: 54 TheMach kernel followed a similar concept by moving the APIs to components which operated in user mode as applications, these could be changed and new ones could be added. This principle was applied to Windows NT.[8]: 6
Despite all these goals, the performance of the operating system was optimized where possible, by adapting critical sections of the code to fast execution speed. To improve networking performance, large parts of the networking system were moved to the operating system core.[8]: 12
Windows NT was designed as a networking operating system. In this branch,Novell had a lead with its productNetWare, mostly because of a lack of competition, and Microsoft failed to develop a product which could challenge NetWare's lead. Cutler hoped to gain additional customers with a reliable networking operating system.[6]: 65 Bill Gates already dominated the market of desktop operating systems with MS-DOS and Windows and hoped to do the same in the networking market with Windows NT.[6]: 3 He especially hoped to find a market in the emerging number of servers, while at the same time he did not expect a success in the desktop market until 1995.[6]: 151
Therefore, Windows NT was positioned as a high-end operating system in an interview with the product manager David Thacher. It was not designed to replace Windows 3.1 completely, but it should rather supplement Microsoft's product palette with an operating system for critical applications. The expectations were 10% to 20% among all Windows sales[29] and a market share of 10% in the high end market, which amounted to one million copies.[32]
While Windows NT 3.1 uses the samegraphical user interface as Windows 3.1, it was developed anew. The operating system is not DOS-based, but an independent 32-bit operating system; many concepts were taken from Cutler's previous operating system,VMS.[31] Thearchitecture of Windows NT takes some ideas of theclient–server model, like the modular structure and the communication between the modules.[8]: 20 System resources like memory, files or devices are viewed asobjects by the operating system, which are all accessed in the same way throughhandles and which can in this way be secured against unauthorized access.[8]: 22–23
The operating system was designed for multiprocessor systems; it supportspreemptive multitasking[8]: 92 and can make use ofthreads to run multiple processes in parallel.[8]: 94 Usingsymmetric multiprocessing, the processing usage is evenly distributed among all available processors.[8]: 24 Theinter-process communication in Windows NT 3.1 is designed around networks; two newly introduced functions,Remote Procedure Call (RPC) andNetwork DDE, an extension ofDynamic Data Exchange (DDE), facilitate the access and data exchange between processes running on different computers inside a network.[33]
The operating system is designed to combine certain elements of amonolithic kernel and a microkernel;[8]: 20 nowadays this is most often referred to as ahybrid kernel.[34] Thehardware abstraction layer represents the lowermost layer and isolates the operating system from the underlying hardware to make it easy to port the operating system to other platforms.[8]: 30 The kernel running atop only has very basic functions likeinterrupt management and processor synchronization. All other functions of the operating system core are handled by modules[8]: 20 which operate independently from one another and can be swapped without affecting the rest of the operating system.[8]: 28
Positioned above the operating system core are the subsystems. There are two types of subsystems: one are theintegral subsystems, which perform important operating system functions. One such subsystem is the security subsystem, which handles the logon process and monitors the security of the system. The other type of subsystem is theenvironment subsystem, which exposes the operating system functions to applications viaapplication programming interfaces.[8]: 27 The base subsystem is the 32-bit subsystem which runs 32-bit applications written for Windows NT. Windows NT applications can only run on one platform, and must be recompiled for every platform. The 32-bit subsystem also contains alloutput functions, including theGraphics Device Interface (GDI),[35] so all other subsystems have to call the 32-bit subsystem to be able to output text or graphics.[8]: 33 Other subsystems contained in Windows NT 3.1 are the POSIX subsystem, which supports POSIX-compatible applications built for Windows NT, and, in the x86 version only, the OS/2 subsystem, which allows command-line based OS/2 1.x applications to run.[35]
TheVirtual DOS Machine (VDM) is sometimes also viewed as a subsystem, but is, strictly speaking, a normal 32-bit Windows application. It manages applications originally built for DOS. Built on top isWindows on Windows (WoW), which allows applications built for 16-bit Windows operating systems like Windows 3.1 to run. On x86 computers, the virtual DOS machine uses thevirtual 8086 mode to run DOS applications directly,[35] on RISC computers, an emulator licensed fromInsignia Solutions is used which emulates a80286 processor. However, not all DOS and 16-bit Windows applications can be run on Windows NT 3.1 due to various limitations,[36] one of them being the inability of applications to directly access the hardware. As well,VxD files sometimes needed by applications cannot be used with Windows NT 3.1.[37] While pure DOS applications are run in separate memory spaces, 16-bit Windows applications have to share one memory space. While this is done due to compatibility reasons with applications which depend on this ability, likeSchedule+ andMicrosoft Mail, it also means that 16-bit Windows applications only run incooperative multitasking. A faulty 16-bit Windows application is in this way able to cause all other 16-bit Windows applications (but not Windows NT itself) to crash.[35]
Windows NT 3.1 provides aboot manager calledNTLDR which is loaded during the startup process of the operating system on x86-based computers. It allows a multiboot setup of multiple instances of Windows NT 3.1, as well as MS-DOS and OS/2 1.x.[38] NTLDR is not used for the RISC versions because the RISC computers'firmware provides their own boot manager.[39]
Every user has to log on to the computer after Windows NT 3.1 is booted up by pressing the key combinationCtrl+Alt+Del and entering the user name and password. All users have their ownuser account, and user-specific settings like theProgram Manager groups are stored separately for every user. Users can be assigned specific rights, like the right to change thesystem time or the right to shut down the computer. To facilitate management of user accounts, it is also possible to group multiple user accounts and assign rights to groups of users.[35]
Windows NT 3.1 introduced the newNTFS file system. This new file system is more robust against hardware failures[8]: 10 and allows assignment of read and write rights to users or groups on the file system level.[35] NTFS supports long file names[35] and has features to accommodate POSIX applications likehard links.[8]: 39 For compatibility reasons, Windows NT 3.1 also supportsFAT16 as well as OS/2's file systemHPFS,[35] but does not support long file names on FAT file system (VFAT). This was added in Windows NT 3.5.
Designed as a networking operating system, Windows NT 3.1 supports multiplenetwork protocols. BesidesIPX/SPX andNetBEUI, theTCP/IP protocol is supported allowing access to the Internet.[35] Similar toWindows for Workgroups, files and printers can be shared and the access rights and configuration of these resources can be edited over the network. When a network printer is installed, the required drivers are automatically transferred over the network, removing the need to manually install the drivers for every computer.[35] TheRemote Access Service (RAS) allows a client from outside the network to connect to the network using amodem,ISDN orX.25 and access its resources. While the workstation allows one RAS connection at a time, the server supports 64.[35]
Windows NT 3.1 supports the then-newUnicode standard, acharacter set which allows multiple languages to be displayed. This facilitateslocalization of the operating system.[40] All strings, as well as file and folder names, are internally processed in Unicode,[8]: 43 but the included programs, like theFile Manager, are not Unicode aware, so folders containing Unicode characters cannot be accessed.[41] For demonstration purposes, aUnicode typeface calledLucida Sans Unicode is shipped with Windows NT 3.1[42] even though it is not installed by default. The previouscode pages are still supported for compatibility purposes.[40]
TheWindows registry, introduced with Windows 3.1, is a central, hierarchical configuration database[35] designed to allow configuration of computers over the network[6]: 251 and to replace the commonly used text-based configuration files, likeINI files,AUTOEXEC.BAT andCONFIG.SYS.[8]: 327 Using the undocumented registry editor, the Windows registry can be viewed and edited by the user.[35]
TheAdvanced Server is designed to manage the workstation computers.[35] It can function as aDomain controller, where all users and groups as well as their rights are stored. This way, a user can log on from any computer in the network, and users can be managed centrally on the server. Trust relationships can be built to other domains to be able to exchange data cross-domain.[35] Using thereplication service, files like logon scripts can be synchronized across all computers on the network. The Advanced Server supports theAppleTalk protocol to allow connections to Macintosh computers.[35] Hard drives can be combined toRAIDs in Windows NT 3.1 Advanced Server, the supported configurations are RAID 0, RAID 1 and RAID 5.
Windows NT 3.1, for the most part, comes with 32-bit versions of the components featured in Windows 3.1 and Windows for Workgroups. However, it also included applications specifically aimed at the needs of Windows NT, like the User Manager, thePerformance Monitor, the Disk Administrator, theEvent Viewer and theBackup application. TheAdvanced Server contained further, server-specific administration tools. Because Windows NT 3.1 is not DOS-based, a new 32-bit command-line processor, calledCMD.EXE was included which was compatible with MS-DOS 5.0.[35] For compatibility reasons, Windows NT 3.1 shipped with a few 16-bit applications, likeMicrosoft Write orEDLIN.[43]
Windows NT 3.1, being an all-new operating system for which no previous MS-DOS based drivers could be used, includes a wealth of drivers for various common components and peripherals.[36] This includes commonSCSI devices like hard drives, CD-ROM drives,tape drives andimage scanners,[44] as well asISA devices like graphics cards, sound cards and network cards. TheEISA bus, is supported by Windows NT 3.1. ThePCI bus, however, is not supported by kernel, but supported by third-party drivers.[45] Windows NT 3.1 supports anuninterruptible power supply.[8]: 328
Windows NT 3.1 could be installed either by using the CD-ROM and a providedboot disk, or by utilizing a set of twenty-two 3.5" floppies (twenty-three floppies forAdvanced Server). Windows NT 3.1 could also be installed over the network.[35] A coupon was included that made it possible to order a set of twenty-seven 5.25" floppies (or twenty-eight floppies forAdvanced Server).[46] Compared to the floppies, the CD-ROM contained additional drivers and applications.
Windows NT 3.1 does not supportATAPI CD-ROMs.
Windows NT 3.1 supports multiple platforms: Aside from the x86 architecture, it runs on computers withDEC Alpha orMIPS (R4000 andR4400) processors.[47]
Minimum system requirements on x86 systems include a 25 MHz80386 processor, at least 12 megabytes of memory, 75 megabytes of hard drive space, and a VGA graphics card.RISC systems require 16 megabytes of memory, 92 megabytes of hard drive space, and a CD-ROM drive.[48] TheAdvanced Server edition requires an 80386 processor with 16 megabytes of memory and 90 megabytes of hard drive space. On RISC systems, 110 megabytes of hard drive space is needed.[49]
Windows NT 3.1 supports dual processor systems, while theAdvanced Server edition supports up to four processors. Due to an error in the processor detection routine, Windows NT 3.1 cannot be installed onPentium II or newer processors. Microsoft never fixed the problem, butunofficial patches are available.[48]
Windows NT 3.1 sold about 300,000 copies in its first year.[50] The hardware requirements were deemed to be very high at that time; the recommended system requirements of a 486 processor with 16 megabytes of memory were well above the average computer's configuration,[36] and the operating system turned out to be too slow to use.[51] 32-bit applications which could have used the capabilities of Windows NT 3.1 were scarce, so users had to resort to the old 16-bit applications; however, these ran slower than on Windows 3.1. Estimates in November 1993 counted only 150 Windows NT applications.[52] Common types of software, likeoffice suites, were not available for Windows NT 3.1.[36] During the development of the operating system, the API calls were changed so 32-bit applications built on the 1992 pre-release version of Windows NT 3.1 could not be run on the final version. This affected software such asMicrosoft Visual C++ 1.0 and Microsoft Fortran PowerStation.[53]
RISC systems with Windows NT 3.1 had an even bigger disadvantage: even though they were more powerful than x86 systems,[33] almost no 32-bit applications or drivers were ported to these platforms.[50] 16-bit applications ran much slower under RISC systems because of the 80286 emulation compared to x86 systems which could run 16-bit applications natively,[33] and DOS and 16-bit applications which depended on 386 calls could not be run at all on RISC systems.
However, not all reception was negative; the multitasking capabilities of the operating system were rated positively, especially compared to Windows 3.1.[35] Compared to the size of the operating system, the installation turned out to be very easy, even though installing from floppies was a very time-consuming task.[54] TheAdvanced Server, intended to be the successor to the unsuccessfulLAN Manager product, was technically much superior to its predecessor, and only failed to gain success because it shared the same problems with its workstation pendant, such as the low performance running 16-bit applications.[55] TheAdvanced Server provided a financial advantage for large networks because its price was not dependent on the number of clients, unlike its competitor Novell NetWare.[49]
With Windows NT, Microsoft entered a market it could not previously address and which was mostly dominated by Unix, Novell NetWare and OS/2.[56] A test performed by theInfoWorld magazine in November 1993, where the networking capabilities of several operating systems were tested, showed that Windows NT 3.1 was seriously lacking in inter-client communication: it could only connect to its own server viaNetBEUI; attempts to connect to Unix, NetWare and OS/2 all failed because no client software was available. For theAdvanced Server, only their own client, the Macintosh and, if only limited, OS/2 were able to connect to the server.[57]
Even though the operating system's actual success was only moderate, it had a huge lasting impact. Developers of Unix derivations for the first time strived to standardize their operating systems, and Novell was so concerned about its market share that it bought a Unix vendor.[6]: 303 Manufacturers ofmicroprocessors hoped to use the portability of the new operating system to increase their own sales,[6]: 303 and thus ports of Windows NT were announced for various platforms, like theSun SPARC architecture[58] and theClipper architecture.[59] It was recognized that Windows NT would dominate the desktop market as soon as the hardware became powerful enough to run the operating system at an acceptable speed.[60] Eight years later, Microsoft would unify the consumer-oriented Windows line (which had remained MS-DOS based) with the NT line with the October 2001 release ofWindows XP—the first consumer-oriented version of Windows to use the NT architecture.[61]
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