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Hard Drive Capacity Confusion, Lucidly Explained

mrklin writes "James Wiebe of wiebetech.com has written a clear example of how hard drive capacity is calculated (PDF file) by hard drive manufacturers (base 10) and OS (base 2). He failed to name how the capacity should be described, though."

9 of 482 comments (clear)

  1. Does it matter anymore? by Dancin_Santa · · Score: 5, Insightful

    With storage prices falling through the floor, does it matter to anyone except whiny nerds whether the byte counts are done in base 10 or base 2?

    In the words of William Shatner, "Get a life!"

    1. Re:Does it matter anymore? by Theatetus · · Score: 4, Insightful
      But the point remains that the HD sellers are using the wrong count and the question that comes to the person who knows is "why?". The answer is simple - to mislead

      Maybe I'm being a naive optimist here, but there seems to be a much more sensible reason:

      The way memory is addressed makes it convenient to use the base-2 units.

      Storage is not addressed in a way that makes it particularly convenient to use base-2 units.

      Got that? That's why we use them on memory. Storage is not addressed that way, so like everything else we tend to use base 10 to describe it.

      --
      All's true that is mistrusted
    2. Re:Does it matter anymore? by ergo98 · · Score: 5, Insightful

      "In reality it seems that they want to sell product with decimal G capacities but have customers believe they are buying disk with conventionally calculated capacity and hoping that no one would notice."

      This is all so absolutely ridiculous. Firstly, about 99% of people on the streets, including most computer users, aren't mentally calculating the power of 2 capacities when you say that a hard-drive has 40GB, or a memory module has 512MB -- Instead they mentally have an awareness that 40GB is "big, but 80GB is better", and "512MB is good". I highly doubt they're going to get their shiney new drive, and DRATS! - they have 42949672960 of virus filled emails to fit in there, but instead they only got 40000000000.

      Secondly, hard drive manufacturers, as a general rule, have used the power of 10 rule since before I first became interested in computers about 18 years ago - this is the standard, and if you haven't read the byline "GB refers to 1,000,000,000 bytes" then you just haven't been looking.

      This whole campaign is just contrived and attention seeking nonsense. I suspect that someone just finished their "Computers 101" course, and they think they've discovered an amazing fraud being perpetrated upon the public by those dastardly harddrive manufacturers.

  2. Ditch binary units by achurch · · Score: 4, Insightful

    As far as ordinary users (i.e. anyone who doesn't have to deal with TLBs, memory pages, disk sectors and the like) are concerned, there's really no reason left to use binary units; 2^9 bytes per sector, 8 sectors per filesystem block, etc. are all low-level conveniences that the user shouldn't have to even notice. Though I personally am too used to the binary units to switch easily, the vast majority of users probably wouldn't even notice the difference, aside from their computers finally reporting the right size for their hard disks. Granted, overcoming the huge momentum for binary units will be difficult, but one could always consider it practice for getting the USA to accept metric.

  3. WTF? by MarvinIsANerd · · Score: 5, Insightful

    This is not a matter of base-10 vs base-2... a base-10 number is written as "2875" for example. A base-2 number is written as "10100110". A base-16 number is written as "8A3F0"...

    This is a matter of UNITS used - like inches vs. feet, or in this case GiB vs GB.

    Geez, get the terminiology right...

  4. I've said this before by Sunlighter · · Score: 4, Insightful

    About two years ago there was a debate about this. Can't remember the details of that debate. Maybe it was when those "mebibytes" were introduced. I still say now what I said then.

    I think there should be "short megabytes" and "long megabytes", and the same for gigabytes. Like this:

    • One short ton is 2,000 pounds and one long ton is 2,240 pounds.
    • One short kilobyte is 1,000 bytes and one long megabyte is 1,024 bytes.
    • One short megabyte is 1,000,000 bytes and one long megabyte is 1,048,576 bytes.
    • One short gigabyte is 1,000,000,000 bytes and one long gigabyte is 1,073,741,824 bytes.
    • One short terabyte is 1,000,000,000,000 bytes and one long terabyte is 1,099,511,627,776 bytes.
    • And so forth...

    Then all we need is to get hard drive manufacturers and OS vendors to state whether they are using short or long tons, er, gigabytes.

    As to abbreviations, take Donald Knuth's suggestion. Use the capital letter twice to suggest binaryness. 1 MMB = one long megabyte; 1 GGB = one long gigabyte. I like this much better than the now-standardized MiB men-in-black abbreviation for long megabytes (which are still not called long megabytes in the standard, they are called mebibytes, which sounds silly and no one uses it).

    Who's with me?

    --
    Sunlit World Scheme. Weird and different.
  5. Re:But seriously by dtfinch · · Score: 4, Insightful

    Those are too hard to pronounce. Who not just distinguish them by prefixing the metric ones with the word "metric", as we do with tons and metric tons.

    kilobyte = 1024 bytes
    metric kilobyte = 1000 bytes

  6. article sidesteps the entire issue by drfireman · · Score: 4, Insightful

    The only relevant issue is the meaning of words like kilobyte, megabyte, and gigabyte. Wiebe describes how you can arrive at two different answers for drive capacity depending on how you define the word "gigabyte," but does so completely uncritically. For example, he describes the drive manufacturer logic and writes that "the drive's claim of 123.5 GB is verified with this simple mathematical formula." But the issue is what the word "gigabyte" means, and the formula presented sheds no light on the word's conventional usage or etymology. I personally was raised to use these terms to correspond the numbers that are powers of two. Wiebe doesn't give me any point of reference to shed light on whether it's reasonable to use the meanings drive manufacturers do. (Of course I already know the answer, but that's beside the point.)

    Wiebe uses some other odd logic, exemplified in point 3.7. He writes that the consumer was never cheated, because a drive advertised as having a capacity of 123.5GB had just that in "decimal based" capacity. This is a bizarre way to characterize the complaints. Consumers who believe they were cheated aren't claiming they didn't get 123.5GB for any definition of the word gigabyte. They're claiming they didn't get 123.5GB by the conventional definition of the word as commonly used in connection with computers. In my view, they're right, although I don't personally get too upset about it.

  7. Re:Naming reference by Piquan · · Score: 4, Insightful

    But personally I strongly reject this "kibibytes" attempt at CS revisionist history. Stick with what CS people have been using as measurements for decades, I say,

    Why shouldn't CS people stick to what the rest of the sciences have been using for decades, that "kilo" means 1000? This CS thing of making "kilo" stand for 1024 is an attempt at revisionist history.

    There's always another perspective.