IBM hard disk drive from 1956


With a capacity of 5 MB, the IBM 350 disk storage unit could have stored about two MP3 files. This photo, showing a unit getting forklifted onto a plane, is from 1956.

IBM's history website has more information about the drive.

IBM 350 disk storage unit (Thanks, Roy Doty!)


  1. As late as 1986 a drive the size of a washing machine with a removable pack that was either 6 or 8 disks held less than a half gig.

  2. Only two mp3 files? That’s the equivalent of one 45 record! Wow, who’s the lightweight music medium now? Er, I mean then? I’m not a time traveller. Honest!

  3. Then there was the interface electronics – another rack of tube gear.

    This much platter area could store about one petabyte these days.

  4. And how long would it have taken the attached computer’s processor to decompress those two mp3s and convert them into an analogue audio signal?

    1. Don’t forget the memory! If the information can’t be processed in real time, you’d need to page all that decompressed audio to RAM.

    2. It looks like the data throughput is about 15 kilobytes/sec. So if it was read and processed in realtime, it would take about 5 minutes. I don’t see how it could have a 600ms seek with only one access arm operated pnuematically.

  5. in 1984 a winchester hard drive for the synclavier synth was about the size of a suitcase and still only 5mb

        1. Perhaps “worship” is not quite the right word.

          AS to computer memory, is there any theoretical limit in sight as to how small we can get them?
          I wonder how long this shrinkage can continue…

    1. In Soviet Russia, cat lols YOU!

      I know, I know, In 1985, that joke was actually funny. Lend me your time machine and I’ll run back and tell it to Reagan.

  6. If you work in the public sector, your office probably had one of these installed in the 60s to run your financial system. Then removed and decommissioned in the 90s.

  7. Oh come on.. who would ever even need 640K? 5 MEGS?? That’s more than you’d ever read.. it’s just an impossible amount of data.

  8. In 1986 I bought a 1 gigabyte drive the size of a suitcase for $10,000. Now its hard to find a 1 gig thumb drive.

  9. Today, a device with 6,400 times that storage unit’s capacity could fit in the space of a postage stamp. Amazing advances in the storage industry!

  10. 1956! That was when I was born. As hard disks got smaller, I got bigger. Is this a Dorian Grey kinda thing?

  11. Agree that’s got to be a drum, not a disk.

    We stored a lot more data per bit then than we do now. Led to some really goofy coding but the more information you could cram into this limited storage medium the better a programmer you were. — Just remember Y2K.

    Also there were 5 and 6 bit bytes on some machines I used.

    Took a corporate level decision to buy more space on the system.

  12. “IBM’s history website has more information about the drive.”…than the drive could have ever held…

  13. Well, you have to compare it to what they had at the time – and even then it sucked. The equivalent amount of information on punched cards would have taken 16 times less room.

    80 bytes per card -> 62,500 cards / 5 MB -> 4″ x 8″ x 0.01″ ~= 3 cu. ft.

    The device in the picture appears to be about 6′ x 4′ x 2′ = 48 cu. ft.

    OTOH, the drum had better access times.

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