The Start of an Empire: MS-DOS Celebrates 30th Birthday

Bill Gates and Paul Allen spent $75,000 for QDOS and began selling sub-licenses for $47,500 in 1981 and $95,000 after that.

IBM was the first customer and received a slightly modified version of MS DOS 1.0 that was offered as PC DOS and sold by IBM for $40. However, Microsoft had sold IBM DOS and BASIC for $400,000 before they actually had access to the DOS operating system. Gates and Allen originally had planned to sell IBM their own Xenix OS, which was derived from UNIX and designed for Intel's 8086 processor, while IBM decided to go with Intel's 8088 CPU instead. Microsoft's solution eventually surfaced as QDOS.

While Microsoft turned DOS into a massive success, Tim Paterson is considered to be the inventor of DOS and wrote the first versions of MS DOS, up to version 1.25. Paterson got out of school in 1978, joined Seattle Computer products and had DOS running on prototypes by January 1979.

Gates initially estimated that IBM could sell about 200,000 DOS PCs, but more than 1 million were eventually sold by the end of 1984. Those first commercial PCs integrated Intel's 8088 processor and ran at 4.77 MHz. The first DOS PC, however, was offered by Seattle Computer products as a set of plug-in cards, including a 8086 CPU card.

Seattle Computer Products wanted $150,000 for the QDOS license, but was convinced by Gates to give it away for $50,000 as well as a $25,000 license fee from a customer that Microsoft kept secret. Sub-licenses for MS-DOS created the first windfall for the young company. In 1981, Microsoft had more than 15 million in revenue.

  • The Greater Good
  • The Greater Good
    @ echo off

    echo I remember back in the day of editing the autoexec and the files just to load the programs that needed all of my 2 megs (yes, two 2 megabytes) of memory. Computers sure have come a long way since my 386 SX-15 (15 MHz) with Windows 3.1 and DOS 5.0.

  • pbrigido
    ah, the good old days of computers. I wouldn't trade in my rig I have now, but I do miss those nostalgic years.
  • dalethepcman
    2megs.. it was all about getting as much out of the first 640k as possible and still having sound and joystick function in your dos games.

    Playing jokes like...
    prompt I know your going to just play strip poker again
    edit autoexec.bat
    @echo off
    attrib +h config.sys
    attrib +h
    echo stop touching me!!!
  • bourgeoisdude
    Starting MS-DOS...
    (dot-matrix printer noises)
    HIMEM.SYS is testing extended memory...done.
  • passingcomment
    I was able to tinker with DOS as a youth on an old workstation my father had lying around. I still remember the hours planning and making file structures, then the hours moving files around until everything was where I wanted them to be. It was fun, and it helped me comfortable with command.
    pbrigidoah, the good old days of computers. I wouldn't trade in my rig I have now, but I do miss those nostalgic years.
  • config.sys
    Add LASTDRIVE=Z so then MS-DOS recognizes some CD-ROM drives like Creative :-)
  • davewolfgang
    I still have a book that has every MSDOS command in up to 6.1 (.2?).

    I found it useful even in XP for some office network mapping on boot (net use lpt3: \\*server name*\hplj4050 - because this old lawyer still likes to use WordPerfect 3.0), but I haven't touched it since 7.
  • I rememeber being poor and getting software meant going to the library, taking out a book and spending days/weeks copying programs out them. The books always had a couple of typos and errors in them which was always fun if someone had not pencilled in the correct character. Machine code was always fun to type.
  • clonazepam
    I remember having that old MS-DOS book that could double as a booster seat... rofl...

    I don't remember exactly how old I was, under 10, and so impressed with myself learning how to partition a 20MB HDD and unzip files! :D