I’ve talked a lot about the advantages and disadvantages of old milestone operating systems. But what were the advantages and disadvantages of Windows NT 3.1? That’s a fair question.

Advantages of Windows NT 3.1

advantages and disadvantages of Windows NT 3.1

Although few people actually used it, Windows NT 3.1 was a landmark release for Microsoft.

Windows NT 3.1 was a landmark for Microsoft: its first fully 32-bit operating system. It was the weird offspring of Windows 3.1, IBM’s OS/2, and DEC‘s VMS. How could it have three parents? Don’t ask. Just smile and nod.

OK, I’ll explain. IBM and Microsoft co-developed OS/2 as a successor to DOS, which was popular but really showing its age by the mid 1980s. But they had a fundamental disagreement over how 16-bit Windows fit into everything. Eventually the disagreements led to a very public divorce that left IBM confused. IBM soldiered alone, developing and eventually releasing OS/2 2.0 and OS/2 2.1, both of which worked rather well and gained a cult following. Microsoft took its nascent code that it intended to form the base of OS/2 3.0, renamed it Windows New Technology, and eventually released it as Windows NT 3.1.

So how does DEC VMS fit in? VMS was (and remains) an operating system for minicomputers. Microsoft hired Dave Cutler, the chief architect of VMS, to be the chief architect of Windows NT. Cutler’s work on VMS and other DEC operating systems influenced the internal workings of NT.

Being 32-bit, it was more stable than 16-bit Windows 3.1. It also had the ability to do something resembling real security. The implementation wasn’t perfect, but the capability was there. It also did real pre-emptive multitasking like OS/2 and Amiga.

Believe it or not, in 1993 there was some question whether Intel would dominate the future of the CPU field. Microsoft hedged its bets by porting NT to any 32-bit chip it could think of. One was MIPS, the chip architecture later used many consumer routers, including the venerable Linksys WRT54G. Another was Power PC, the Motorola/IBM CPU that Apple used in its Macintoshes for about a decade. The third was the ill-fated DEC Alpha, a criminally underrated chip from the 1990s. In 1993, this versatility was an advantage.

Aside from the improved stability and security, it had a new filesystem, NTFS, that was more efficient and faster than the ancient FAT filesystem DOS used.

NT 3.1 was mostly compatible with 16-bit Windows, and its “Windows on Windows” approach to running 16-bit apps was more transparent than OS/2’s approach.

Finally, its user interface was more familiar than OS/2. It was completely different under the hood, but if you could use Windows 3.1, you could use NT 3.1 too.

Disadvantages of Windows NT 3.1

In 1993, memory was expensive, and Windows NT wanted 16 megabytes of it. In 1993, 4 megabytes of RAM was standard and some systems still came with as little as 2.

Setting up NT 3.1 was also difficult, since Plug and Play was still a couple of years off.

Driver support was also anemic. Most consumer hardware didn’t have NT drivers at first, so you had to dual boot with DOS and Windows 3.1 to use a lot of computer hardware we take for granted today.

In the early 1990s when I would get into operating system debates, I advocated for OS/2. People always said, “What about Windows NT?” That was a short argument because I only ever met one person who ran Windows NT 3.1 on a regular basis. I was working at Best Buy and he came in with a pretty long shopping list. But we couldn’t find a sound card, CD-ROM drive, or flatbed scanner that would work with NT 3.1 at the time. Or at least I couldn’t guarantee any of it would work, since it didn’t say so on the box. DOS worked. Windows 3.1 worked. Even OS/2 usually worked. For NT, you were on your own early on. The best case scenario involved lots of hunting for and downloading drivers from BBSes and Compuserve.

Windows NT grew up, but 3.1 was a bit of a rush job and it showed. It was really NT 3.51, released in May 1995, that gained a lot of use, and NT 4.0, released in July 1996, that took Windows NT into something resembling mainstream. For several years, Windows NT was something that people talked about while they ran Windows 3.1 instead.

Windows was one of the most important changes of 1990s computing, and Windows NT had a lot to do with that, but the promise of there someday being one Windows that could be everything to everyone, and delivering it a decade later was probably a once in a lifetime event. Microsoft has to move faster than that today.


Windows NT 3.1 is probably the most influential operating system nobody used. It lived up to its promise, as every Microsoft operating system from Windows XP onward is its direct descendant. If you ever wondered why you have to hit CTRL-ALT-DEL to log in, it was so Windows NT could get C2 Orange Book certification from the U.S. Government.

Windows NT 3.1 was Microsoft’s attempt at a “Unix killer.” That didn’t exactly happen. Both Unix and NT are far, far more widespread now than anyone had any right to imagine in 1993. But NT definitely did put a dent in proprietary Unix. There’s a lot less AIX, Solaris, and HP-UX around today. Much of that is because of Linux, but NT had something to do with it too. And Windows NT turned out to be far, far more successful than Microsoft’s ill-fated Unix product.

Oddly, even though NT was designed to leave Intel behind if necessary, it may have saved Intel’s x86 architecture. Since NT could run on cheap PCs, that was what most people bought, and they put up with the limitations of a $1,500 PC. It wasn’t as good as a $3,000 RISC workstation but it was probably better than half as good. Sustaining that market share gave Intel the cashflow it needed to eventually make x86 competitive with those other chip architectures. You don’t hear much talk of x86 going away anymore.