Western Digital calculates hard drive size

I like to know what the exact size of my 250 Gig WD HD PATA size is for anyone that owns this product? I formatted my drive and it comes back reporting as 232 Gig, it seems I lost over 18 Gig to computer formating. I read somewhere that is it due to ““This is standard industry practice, unfortunately were a drive manufacturer (Western Digital for example) to be honest about this then their drives as advertised would all appear smaller than the competitors, when in fact they would not be. Shoppers would be comparing “apples to oranges” rather than “apples to apples”.”” How true is this statement? So in reality my 250 Gig is really a 232 Gig drive?

My system is:
Win XP pro sp2
AMD 1800+

Every hard drive will show a few GB less than labeled capacity, and the question “So in reality my 250 Gig is really a 232 Gig drive?” is how much usable capacity on the drive. Similarly 700 MB CDs will hold a few MB less than 700 MB capacity for same reasons.

manufacturers measure 1 GB as 10^9 bits (1000000000 bits)
computers measure 1 GB as 2^30 bits (1073741824 bits)

so your computer sees ~7.4% less space than the manufacturer states, this is true for every hard drive and for dvds. in other words, no space is “lost” computers just use a different measure of space

You’re not getting screwed (at least not any more so than the rest of us). This is common practice due to the way the manufacturer’s round their own calculation of a GB not just with WD but across all manufacturers.

as jwill already said you’re not “losing” space since it was never there to begin with. Your computer is reading back the correct amount of space on the disc, it’s the manufacturer that is misreporting it.

While this is standard practice, for people that are unaware of it and/or don’t understand the data measurements, it’s definitely alarming to notice for the first time.

I’m not sure why manufacturer’s are still allowed to do this. I believe there was a court case not too long ago, but I don’t recall the details.

EDIT: I also wanted to add that a lot of people never noticed or simply ignored this issue in the past because it didn’t seem like much. Because the difference in actual size versus size reported increases with the size of the drive, it’s becoming much more noticeable. a “10 GB” drive may actually only show a size difference of a couple hundred megabytes, whereas your 250GB drive is showing an alarming (but normal) 18GB or so difference.

All my 250GB drives - a WD, 3 x Seagate & an Hitachi - are formatted at 232GB.

Exactly correct my WD 250gbs HDD formatted to exactly 232gig. My WD 150gb RaptorX formatted to 139gig.:iagree:

Yep, same here with my Hitachi 250 gig.

Hard drive properties in Windows XP shows my 400Gb Seagate Capacity at 400,085,811,200 bytes or 372GB. It is confusing and I agree they should advertize the size you will see when the drive is installed.

I have WD 250GB drive in a USB2 external enclosure. This is
what the Linux kernel says when I plug it in:

usb-storage: device found at 7
usb-storage: waiting for device to settle before scanning
Vendor: WDC WD25 Model: 00BB-22GUA0 Rev: 0 0
Type: Direct-Access ANSI SCSI revision: 00
SCSI device sdb: 488397168 512-byte hdwr sectors (250059 MB)

As the others have already said, hard-drive manufacturers use
salesman’s gigabytes instead of 1024^3. The formatted capacity
of my drive is:
/dev/sdb1 233G 97G 137G 42% /media/usbdisk

Are you sure? I routinely write the full 700MB+ to 80min CD-R.
360,000 sectors at 2048 bytes per sector = 703ish.

Same here. 703 is about right judging from the ones I’ve burned to capacity in the last week or so.

700 MB / 80 min CD-R media holds approximately 703 MB as others have said, so unlike harddisks and DVD media, the “MB” used for CD-Rs is usually 1024*1024 bytes - properly known as MebiBytes (MiB).

See the article about Binary prefix at Wikipedia for more information about kilo/kibi, Mega/Mebi etc.

nice article. i’ll have to give that a closer read when I have more time, but it certainly looks thorough.

so maybe we should stop complaining about the number of gigabytes on our hard drives and complain about the gibibytes instead :stuck_out_tongue:

Yep! :wink:

Cools, thanks for those who answered my questions that clears alot up now. Reason I asked was I was going to use that 250 for backing up data and as part of my system drive but wasn’t sure if I had to reformat it to make sure I wasn’t loosing any HD space. But now I can ahead move data around with relief. I also did hear about that court case involving misrepresentation of HD space in relation to actually space report after format by computer. So last question it would be better to buy a larger capacity drive cause you won’t notice that lose of space as much if it was a smaller drive, right??

the best thing to do is buy a drive with the space you need (after taking into account the marketing numbers)

the amount of space lost in conversion scales with the size of the drive. It’s proportionally the same. It’s just physically more in a larger drive.

at least one thing we can be thankful for is that it sucks, but it’s a uniform suckiness…so at least when comparing price per GB you don’t have to do extra calculations depending on the brand.

yep, its a constant 7.4% difference, so if you bought 3 250GB drives or 1 750GB drive you would still end up with the same amount of total space (around 696GB)

Every time I try to burn more than about 650 MB to a 700 MB CD, Nero gives message that there is not enough space on the disk. I don’t know why others are able to burn 700 MB unless some 700 MB CDs have more capacity than others. What brands are you using to get the full 700 MB to burn?

You got the wrong area to be posting your question. Read again the head topic.

Wandering further off-topic…
You can get about 650MB of data on a 74 minute CD-R. Are
you sure they are 80 minute CD-R?

This topic probably merits a thread of it’s own. Do you
want to start one one? Possibly in the Blank Media forum.