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

jimbo45 said:

Actually the File system is important -- How do you know that the disk is actually less than 500 GB. Presumably you must have put some data on it or formatted it in some way. All file systems have directory overhead etc which reduce the amount of available DATA space on the disk.

Looking at the packaging of one of my older powered 500 GB USB ext drives I see that the spec refers to 500 GB Unformatted capacity and mentions that the actual amount may be less after formatting it.

The "Native" amount of the disk before you format it can probably be seen in your BIOS before the system boots into the OS.

The measurement here should refect the theoretical maximum capacity of the disk drive (it should show you details such as Sectors / heads / cylinders etc).

Cheers
jimbo

Formatted or non formatted, the capacity of the disk remains 500.000.000.000 bytes.

The fact that after formatting you can't see or use it all,
or that parts of it are occupied, does not change the physical properties of the drive.

The difference in size mentioned by manufacturers, and how it shows in windows has nothing,
I repeat nothing to do with formatting, nor filesystem, nor bios nor anything else.
Note that I am NOT talking about free space. I'm talking about capacity.

The first post of this thread shows you that the difference between advertised and reported by windows,
is because the whole industry (miss) uses 1024 for a kilobyte, and disk makers use 1000.

The calculation is watertight.

Hi there.

Not wishing to flog a dead horse but if Windows reports a drive as only having yyyy bytes then thats all Windows can tell you. Windows can only report what IT sees -- and it DOESN'T see the actual maximum capacity of the drive.

Say the file system was REALLY inefficient and Windows reported a 500GB drive as having 300GB. Who'se at fault here - the manufacurer or the operating system making inefficient use of the drive.

Ok the manufacturers might be using 500 GB as 500GB rather than the normally accepted computer term of 1KB = 1024MB but if it says on the package 500GB UNFORMATTED capacity then in my book you've got 500GB.

How you USE it (or how the OS uses it) is another matter.

If you format the same drive with ext3 on a Linux system and display the amount of space you'll get a different free space indicator than if you format the same device on Windows. Windows will also give you DIFFERENT amounts for the same device depending on the formatting options you chose.

I'm with the manufacturers on this one -- they publish the spec of their drive - they don't know what file system you are going to use on it and in some cases the manual actually says 500GB = 500GB (but of course we all read the manuals every time don't we ).

Cheers
jimbo

jimbo45 said:

Hi there.

Not wishing to flog a dead horse but if Windows reports a drive as only having yyyy bytes then thats all Windows can tell you. Windows can only report what IT sees -- and it DOESN'T see the actual maximum capacity of the drive.

Say the file system was REALLY inefficient and Windows reported a 500GB drive as having 300GB. Who'se at fault here - the manufacurer or the operating system making inefficient use of the drive.

Ok the manufacturers might be using 500 GB as 500GB rather than the normally accepted computer term of 1KB = 1024MB but if it says on the package 500GB UNFORMATTED capacity then in my book you've got 500GB.

How you USE it (or how the OS uses it) is another matter.

If you format the same drive with ext3 on a Linux system and display the amount of space you'll get a different free space indicator than if you format the same device on Windows. Windows will also give you DIFFERENT amounts for the same device depending on the formatting options you chose.

I'm with the manufacturers on this one -- they publish the spec of their drive - they don't know what file system you are going to use on it and in some cases the manual actually says 500GB = 500GB (but of course we all read the manuals every time don't we ).

Cheers
jimbo

You simply don't get it, or don't want to get it.

Either way, I am done explaining.

SquonkSC said:

jimbo45 said:

Hi there.

Not wishing to flog a dead horse but if Windows reports a drive as only having yyyy bytes then thats all Windows can tell you. Windows can only report what IT sees -- and it DOESN'T see the actual maximum capacity of the drive.

Say the file system was REALLY inefficient and Windows reported a 500GB drive as having 300GB. Who'se at fault here - the manufacurer or the operating system making inefficient use of the drive.

Ok the manufacturers might be using 500 GB as 500GB rather than the normally accepted computer term of 1KB = 1024MB but if it says on the package 500GB UNFORMATTED capacity then in my book you've got 500GB.

How you USE it (or how the OS uses it) is another matter.

If you format the same drive with ext3 on a Linux system and display the amount of space you'll get a different free space indicator than if you format the same device on Windows. Windows will also give you DIFFERENT amounts for the same device depending on the formatting options you chose.

I'm with the manufacturers on this one -- they publish the spec of their drive - they don't know what file system you are going to use on it and in some cases the manual actually says 500GB = 500GB (but of course we all read the manuals every time don't we ).

Cheers
jimbo

You simply don't get it, or don't want to get it.

Either way, I am done explaining.

Oooohh, my turn then

Jimbo, mate, me old mucker, let's conduct a thought experiment. Say there's this drive and it just came from the factory, as yet completely undefiled by software. Like, there's nothing on there at all. No OS, no recovery partitions, no vestigal deleted stuff... nada.

Is it meaningful to talk about that drive's capacity yet? Does it have a "size" we could measure in terms of a certain number of bytes?

Most people would agree that the drive is indeed endowed with a certain size even at that point, long before file systems become a concern. That is the quantity whose dimensions are being discussed in this thread, not the formatted capacity or any other FS-specific value.



(Otherwise, if you've discovered a way to prove that the drive's capacity while it's brand spanking new is a probability cloud, we can publish the idea as the "New HDD Capacity Uncertainty Principle" - you can either gauge the drive's position or its size, but not both at the same time.)

I wondered why and now I know. Thanks.

Hi there
in the case of SSD's the argument is clear -- Here's the statement from the Horses Mouth (OCZ).


*Consumers may see a discrepancy between reported capacity and actual capacity; the storage industry standard is to display capacity in decimal. However, the operating system usually calculates capacity in binary format, causing traditional HDD and SSD to show a lower capacity in Windows. In the case of SSDs, some of the capacity is reserved for formatting and redundancy for wear leveling. These reserved areas on an SSD may occupy up to 5% of the drive’s storage capacity. On the Vertex Series the naming convention reflects this and the 30 is equivalent to 32GB, the 60 is equivalent to the 64GB and so on.



For more info

http://www.ocztechnology.com/products/solid_state_drives/ocz_vertex_turbo_series_sata_ii_2_5-ssd

Think this at least for SSD's should wrap this up.

Cheers
jimbo

I am sorry to say it, jimbo45, but that doesnt make your argument clear. It is still a matter of how you interpret the number "500 GB". The harddrive manufacturer interpret it one way and Windows another.

The situation with SSDs is completely different from the situation with rotating platters.

With SSDs the drives are based on a device (the memory chips) that are already in measured in GibiBytes (GiB) and so the "32 gig" is in fact accurate (minus the additional 5% as outlined above).

In the case of SSDs the manufactureres are reporting proper sizes. That is NOT so for rotating drives and never has been all the way back to the first 10 meg drives sold to the PC world.

The manufacturer gets X bytes out of a platter based on how they can pack it on and in order to make the drives sound larger than they are it was a no-brainer to simply report the size in GB which is larger than the size in GiB and it remains that way today.

SSD == Accurate and clear reporting of unformatted drive size.

Rotating Drive == Misleading use of Gigibyte vs Gibibyte, always has been.

Would 1.5TB be 1395GB if I'm correct? I'm setting up a partition so I can format it and trying to as close to capacity as possible.