Windows NT 3.1

Not to be confused with Windows 3.1.
Windows NT 3.1
Version of Microsoft Windows
Logo
Screenshot
OS familyWindows NT
Version3.1
CodenameRazzle
Preliminary nameOS/2 3.0
Advanced Windows[1]
Architecturex86, DEC Alpha, MIPS
Latest build3.10.528.1 (Service Pack 3)
Release date1993-07-27
Support end2000-12-31
Replaced by
Windows NT 3.5x

Windows NT 3.1 (codenamed Razzle) is the first version of Windows NT. It had a very similar interface to Windows 3.1 but unlike Windows 3.1, Windows NT 3.1 was a complete 32-bit operating system while Windows 3.1 was mostly a constrictive 16-bit environment, although it also included 32-bit components to take advantage of the 386 processor. The name NT officially stands for "New Technology", although it has also been explained to stand for N-Ten, the codename for the Intel i860 processor that NT was originally designed for. It was succeeded by Windows NT 3.5 in 1994, and is the first version of Windows NT to support upgrade paths to Windows NT 4.0. Several update packages were released for NT 3.1 during its lifetime.

Microsoft initially developed NT with the intention to use it as the base for OS/2 3.0, with the project being also known as NT OS/2 or Portable OS/2. However, with the high sales success of Windows 3.0, Microsoft changed the NT OS/2 plans to turn it into a 32-bit version of Windows with a subsystem to run existing OS/2 apps, which largely contributed to the end of the IBM-Microsoft partnership. The project was commonly referred to as Advanced Windows in the press before its final name was unveiled. The operating system was publicly demonstrated for the first time at COMDEX in October 1991. At the Win32 PDC conference in June 1992, Windows NT was demonstrated for the x86 and MIPS processors. On 27 July 1993, Windows NT 3.1 was released for x86 and MIPS, followed by the DEC Alpha version in September. The Workstation version was sold at $495 while the server version was sold for $1495.

The boot screen only shows the processor count if a multiprocessor kernel and HAL is being used, which would be the case on systems like the Compaq SystemPro/XL and its clones.[2]

System requirements[edit | edit source]

The x86 version of Windows NT 3.1 requires an 80386 processor with D1 stepping, at least 16 MB of RAM, 75 MB of hard drive space, and a VGA or better display.

The MIPS and DEC Alpha versions require at least 16 MB of RAM and 92 MB of hard disk space.

Hardware compatibility[edit | edit source]

Windows NT 3.1 does not support processor generations higher than the original Pentium due to a faulty processor check during setup. Windows NT will state the processor as incompatible and abort setup without additional patching of setup files. Additionally, the x86 version of Windows NT 3.1 does not recognize more than 64 MB of RAM unless the OS/2 DRAM compatible mode is enabled in the BIOS.[3][4]

Windows NT 3.1 does not contain support for ATAPI CD-ROM drives by default, requiring either a SCSI CD-ROM controller or an ATAPI driver to be provided during setup in order to install.

History[edit | edit source]

In late 1988, a group of engineers led by Dave Cutler left Digital Equipment Corporation for Microsoft following the cancellation of the PRISM and MICA projects. At Microsoft, they formed the Portable Systems Group tasked with creating a portable 32-bit version of OS/2. The new operating system, called NT OS/2 or Portable OS/2, was designed to support multiple personalities: aside from support for both 16-bit and 32-bit versions of the OS/2 API, it would also include a POSIX personality, which would allow Microsoft to run for US government contracts. Commercial release was planned for the early 1990s with NT shipping as OS/2 3.0, while IBM was adding 32-bit support to the original OS/2 codebase to create OS/2 2.0.[5]

Originally, NT targeted the Intel i860 XR processor (codenamed N10 or N-Ten, one of the discussed origins of the "NT" acronym). Alongside the operating system itself (codenamed "Razzle"), the team also designed a i860-based motherboard codenamed "Dazzle" that was used for internal testing once engineering samples were available. When the performance of the i860 was found to be disappointing, NT was ported to the MIPS R3000 processor. A new motherboard codenamed "Jazz" was also designed by reengineering Dazzle for the new processor. The system was then ported to the i386 in early 1990. Together with the port, it was also converted from big to little endian.

After the successful launch of Windows 3.0 in May 1990, it was decided to add support for a Windows personality, first as a peer to the OS/2 personality.[6][7] By August 1990, the main focus of the NT project changed to creating a 32-bit version of Windows,[8] while the OS/2 subsystem was eventually reduced to character mode OS/2 1.x application support.

List of known builds[edit | edit source]

Pre-ePDK[edit | edit source]

September 1991 beta (ePDK)[edit | edit source]

October 1991 beta (PDK1)[edit | edit source]

December 1991 beta (PDK2)[edit | edit source]

April 1992 beta[edit | edit source]

June 1992 beta (Preliminary Release for Developers)[edit | edit source]

October 1992 beta[edit | edit source]

March 1993 beta[edit | edit source]

April 1993 beta[edit | edit source]

June 1993 beta[edit | edit source]

Pre-RTM[edit | edit source]

RTM[edit | edit source]

East Asian Beta[edit | edit source]

East Asian RTM[edit | edit source]

Service Pack 1[edit | edit source]

Service Pack 2[edit | edit source]

Service Pack 3[edit | edit source]

References[edit | edit source]