HDD's - the Advertized size vs the Actual size.

[fseal]

Why lie about the number then post a disclaimer which doesn't even accurately cover the lie?

Look, they put the size on there and advertise the size of the drive as if there is such a thing as a base 10 computer. If there was, the number would be correct (with the disclaimer)! But in EVERY case those drives are being put in to base2 computers with base 2 hardware. The HARDWARE removes 3-4 % of that number right off the top even when there is no OS involved. There is NO CASE where you can get anything close to the advertised size (in "k").

The number they advertise should be in binary gigabytes (GiB) and NOTHING ELSE. /Then/ the disclaimer needs to stay to explainin away the additional 4% (or so, it varies) loss that IS due to the OS's filesytem.

I still put it to the drive companies that they should not only come clean with the Base10/Base2 numbering issue but a /smart/ company would create drives that allowed them to advertise "true" post formatting numbers!

Being able to advertise "True Terrabyte Drives" would be marketing genius! Imagine how happy people would be to install and format their "1 terrabyte" drive and ACTUALLY GET A TERRABYTE OF DATA STORAGE out of it?!?!? Seems like a company people might want to go back to and buy more drives from to me...

 

[Night Hawk]

They are not lying. To actually get 920gb you have to design and machine a drive in decimal to a higher rounded figure. You seem to forget the mechanical and tooling side of manufacturing. The standards and methods of measurement have to be by physical not binary methods.

They won't be using something like 1.2tb but a rounded off capacity there as well as what is seen as a manufacturing standard as well as the marketing side. IF you need a full 500gb+ you would go with the next drive size of 640gb or 750gb.

For a full 1tb you would then go to a 1.5tb model since once a drive is filled to the max it becomes inaccessible and typically sees the "out of memory" type errors. In other words you plan on buying a drive with a litle over the amount of space you need. You wouldn't be able to fit 750gb of data on a "true 750gb" drive there meaning the next size up would be needed even if only 920gb available.

 

[pparks1]

fseal,

If you are interested, if you buy OSX Snow Leopard, it displays a 1TB drive as 1TB when formatted.

 

[fseal]

The fact that OSX displays drive sizes in base 10 (if thats true) and lies about it's own formatting usage too? is actually kind of disturbing.

I can find no logical reason that any combination of electrical, chemical or physical properties would /require/ a drive to be manufactured to build drives to base 10 numbers of storage units rather than Base 2.

It is PURELY a marketing issue to make the drives meet certain numbers and those numbers chosen have traditionally been base 10 simply because it was a slighly easier target to hit. There is absolutely nothing about physics that demands that drives be manufacturered to 1TB instead of 1 TiB. They /target/ 1TB and build to that number.

Drive densities are increaing all the time. I can't believe that that extra 3% or 7% (depending on your goal of presenting honest numbers) is so completely out of the range of physical reality that is has been impossible to ever properly label drive capacites as they are actually used by consumers...

 

[pparks1]

Obviously there is no right or wrong answer here. Consumers have felt they were mislead for years and all manufactures continue to label their drives the same way they always have.

The word kilo has been used as an SI standard for a very long time to mean 1,000. It does not actually mean, 1,024 as a computer would read it.

As a consumer, I'd much rather say that I purchased an 80GB hard drive rather than saying that I just purchased a 74.59236587 GB hard drive. It's just so much simpler.

I'd feel that this was marketing if hard drive manufacturers made a change from base 2 to base 10...but it's always been base 10. Then, they put a disclaimer on the box explaining how they arrived at the drive size. They didn't change midstream when they realized it would make them look better. And tell me why a hard drive mfg like Samsung doesn't take a firm stand and advertise their drives as 74GB and let the rest of the industry continue to just say 80GB? Don't you think "some" people would buy that 74GB drive out of principal...because they didn't feel mislead.

Trust me, I've seen the posts on the Apple forums where Snow Leopard fanboys say that "with their coveted machine", an 80GB hard drive gives you all 80GB. Rest assured that drive has exactly the same amount of space available as any other drive under any other OS and you will store exactly the same amount of data.

If you consider how you look at a file, if you see a file that is 1,000,000 bytes...would you not say that it's 1 megabyte in size. Or would you instead say that it's 95.3674316% of 1 megabyte since 1 megabyte to the computer is actually 1,048,576 bytes.

Another way to look at this, lets say that you have a movie file on your computer that is exactly 200GB in size. Windows would display this file as 214,748,364,800 bytes. I think most people would eye ball that file and say it's 214GB in size....and they would likely be shocked and amazed when that 214GB file fit on their 200GB Seagate hard drive. But trust me, it will fit, as 214,748,364,800 bytes is exactly the same size as a hard drive advertised as 200,000,000,000 bytes in size. It's exactly the same thing. You haven't lost 1 single solitary byte.

 

[Night Hawk]

VelociRaptors have a 74gb model. That's not an even 80gb but 68.91787052154541gb in actuality. As far as a video 214,748,364,800 bytes in size most would more likely see that rounded off to 414.75gb +or- a few bytes.

The marketing decision is mainly geared towards novice not advanced users looking at how to calculate actual sizes as well as the standards used in manufacturing.

 

[GeneO]

If you wonder why your 500 Gbyte disk only reports 465 Gbyte in your system, read on.​

   Information

A drive that is advertised as a 500 Gbyte actually contains 500.000.000.000 bytes

The manufacturers just divides it three times by 1000 to show the value in Gbytes, but that's not accurate.​

   Information

1 Gbyte = 1024 Mbyte,
1 Mbyte = 1024 Kbyte
1 Kbyte = 1024 byte

To calculate the actual size we need to divide it three times by 1024.​

   Information

500.000.000.000 byte / 1024 = 488.281.250 Kbyte

. . 488.281.250 Kbyte / 1024 = . . . 476.837 Mbyte

. . . . .476.837 Mbyte / 1024 = . . . . . . 465 Gbyte

The actual size of the disk is not 500 Gb, but 465 Gb
With a 1TB disk it's the same thing, because 1 Tbyte = 1024 Gbyte
A 1Tb disk is actually only 1000.000.000.000 byte, which equals 0,9 Tb (931 Gb)
You actually get 69 Gb less than you thought you paid for.​

.

An alternative method to calculate the real size is to use ratios: thanks to Airbot​

   Information

For Gbyte the ratio is 0.9313226

500 Gbyte multiplied by 0.9313226 = 465.6613 Gbyte

   Information

For Tbyte the ratio is 0.9094947

2 Tbyte multiplied by 0.9094947 = 1.8189894 Tbyte or 1,819 Gbyte

.

I didn;t follow any f the threads here, so I may be repeating ... sorry.

The standard convention and nomenclature now is (^ denoting exponentiation):

1GB = 10^9 bytes
1GiB = 2^30 bytes
1TB = 10^12 bytes
1 TiB = 2^40 bytes
1 PB = 10^15 bytes
1 PiB = 2^50 bytes

So if an manufacturer is specifying 1 Tb you can be pretty sure it is 10^12 bytes, not 2^40 bytes

- Gene

 

[Night Hawk]

Manufacturers advertize the rounded off figure not the actual amount of bytes seen using the decimal unit of measurement. A 500gb drive in bytes when looking at a post screen for example would show 500,000,xxx,xxx with the Xs representing numbers other then 0s being seen showing the actual figure is over 500 billion.

Note that uses the rounded to 1000 not 1024 figure with the physical form of measurement in decimal while the OS uses the binary form. People forget there are two totally different methods being used for calculating drive capacities. The decimal form is based machine tool standards not OS standards simply being rounded off to the 500gb figure.

 

[alfranatic]

Brilliant,thanks for this nice insight.
I noticed the differences,but now i have some answers.
Good job.Thanks
BTW,even with similar hdd's,let's say each 1 TB,there are differences..I wonder..

 

[Night Hawk]

Some years back when running a WD 250gb drive I was seeing some 234gb available while some running Seagate were typically seeing 232gb. You will note small variances between companies as well as various model drives at times but minor.

 

[funkybassist]

I already knew this but I'm going to link it to some friends that don't know

 

[TheBetaFox]

Well, I didn't lose a lot when I got a 250 GB laptop HDD, did I?

 

[LoWang]

I am sorry to bump this, but SquonkSC you should pay more attention if you write such guides. You keep mixing GB with Gb and TB with Tb! This is not very right, because you confuse bytes with bits this way. And you cannot say that it does not matter, because it always means bytes! See some articles about new hard drives or memory card technology and you will notice they always declare data density in Gb (Gigabits) per inch. Just a friendly but important notice IMO...

 

[Jay10]

So according to the first post, a harddisk with an advertized size of 640 GB would have an actual size of 596 GB, right?

I'm asking because my Acer laptop had 556 GB from the beginning, despite having an advertized size of 640 GB.

 

[profdlp]

Jay10, there's probably a hidden partition with stuff needed for the Acer Restore business that uses the rest. Look in Disk Management and see if you can spot it there.

 

[Britton30]

LOL

Some is file system overhead, the rest was all lies

You have a very accurate hammer!!

 

[Britton30]

Confusin' ain't it?

A little primer for you novices who may not know, I'm not meaning to belittle anyone. Just explainin'. This took me some time to understand too.

Computers understand the binary number system, only two numbers, 0 or 1. All data on your computer is in bits, a 0 (zero) or 1 (one), or on or off. A bit is represented by the lower-case "b".

Eight bits= 1 Byte, or character and is represented by the upper-case "B". As you double this over and over, 2,4,8,16,32,64,128........you'll get to 1024, which is 1KB to the computer. This means K, kilo, 1024 Bytes. Continue the doubling and you get to 1,048,576 which is a binary Mega Byte, MB.
1024KB=1 MB, 1 million binary bytes or Megabyte, 1024MB=1GB, or Gigabyte, one billionbinary bytes, 1024 Gigabytes=1TB, 1 Trillion binary bytes or terabyte.


HDD makers use the metric system to describe drive sizes:
KB= 1,000 bytes
MB=1,000,000 (million) bytes
GB=1,000,000,000 (billion)bytes
TB=1,000,000,000,000 (trillion) bytes

When you buy, say, a 500GB drive it in fact has 500 billion bytes, but counted in the metric system. In the binary system, which you computer reports, it is shown as about 465.661 GB. No one is "cheated" per se, but speaking different languages, binary and metric. It is misleading however if you don't understand why your shiny new 500GB drive says it's only 465GB.

It seems RAM, your memory, is sold with binary designations. That is, 1GB of RAM is in fact 1,073,741,824 bytes and not 1,000,000,000 bytes.

Hope this helps out.:banghead:

 

[dogbert2]

My new Seagate Barracuda LP 2TB (model number ST32000542AS) is being formatted right now, the final formatted capacity will be 1863.01GB (per Disk Management).

On the bright side, Windows 7 x64 Ultimate saw the drive perfectly and installed the necessary drivers (no fuss, no muss)

 

[sweetnightmare]

hello guys,

info query..

i am owning an i5 500G laptop...
my problem: usable space is only 407G ...

by looking on the disk management, 50G is FAT32... the 407G i said above is NTFS...

what happen to the 43G?? (i do know i cannot fully utilize the 500G as what stated above)...

can i reduce the 50G FAT32?

 

[ignatzatsonic]

The formatted capacity of a 500 GB drive is about 465 GB.

What is on the 50 GB FAT 32 partition? Why do you have it? Is this a second hand computer? Most partitions on most PCs are NTFS.

Post a picture of what you are seeing in Disk Management.