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GeoffW
06-02-2004, 04:34 PM
Hi

I have a one week old Dell Dimension 2400 P4, 512Mb, 40GB hard drive & Windows XP Home. I am trying to put a 120GB drive in as a slave drive. I want it to be the slave to store my video files. The computer sees it and the BIOS says it is a 120GB. Yet when I format it using either fdisk or XP's computer management all it will format is 111.78GB's. I have tried setting it up as two seperate partions but when added each partion still only makes up 111GB's. This is the second hard drive as both me and the shop suspected a faulty hard drive which obviously is not the case. It is a Western Digital WDC WD1200BB. I guess the question I am asking is where is my missing 9GB's Surely FAT32 or NFTS does not flog 9GB's

Thanks

PoWa
06-02-2004, 04:38 PM
The hard drive manufacturers use different ratings for how they measure the 120gbs. For example they might measure 1000mbs = 1Gb. Whereas windows and everyone else uses the standard 8bits to a byte so 1024Mbs = 1Gb.

So nothing wrong with your drive. I have a 120Gb drive and it gets measured as 111Gb by windows too.

GeoffW
06-02-2004, 04:43 PM
Thank You PoWa. Nice to know I'm not going nuts.

Phar
06-02-2004, 05:32 PM
Got a 120GB HDD too just added up the drive sizes and only comes up to 111.6GB. What a rip LOL

Lizard
08-02-2004, 09:22 AM
> The hard drive manufacturers use different ratings
> for how they measure the 120gbs. For example they
> might measure 1000mbs = 1Gb. Whereas windows and
> everyone else uses the standard 8bits to a byte so
> 1024Mbs = 1Gb.
>
> So nothing wrong with your drive. I have a 120Gb
> drive and it gets measured as 111Gb by windows too.

Maybe my math is wrong, but that would mean for every "windows" gigabyte, you lose 24Mbs. 24Mbs x 120 = 2880Mbs, which is a far cry from 9Gbs of lost space. So where would the other 6 Gbs go?

Lizard

agent
08-02-2004, 09:43 AM
No...

Er, actually, there must be something wrong with my maths too! :)

I know for a fact on a 120GB drive, you only actually get about 111GB storage, but I just can't seem to prove it via maths - even working on a 40GB drive I can't get it to work out (and I've done the maths to prove it before, too).

Terry Porritt
08-02-2004, 10:55 AM
The manufactures always try to make their drives sound bigger for some reason, must go back to the days when 8MB was humongous :)

So in addition to them using 1000MB=1GB, they also quote the unformatted capacity.

The formatted capacity is less because space is lost defining the boundary between sectors.

If you look at a carton of floppy disks for example, it will say 2MB.

Terry Porritt
08-02-2004, 10:57 AM
Oops, some floppy cartons say 2MB, when the formatted capacity is 1.44MB

Lizard
08-02-2004, 02:15 PM
> No...
>
> Er, actually, there must be something wrong with my
> maths too! :)
>
> I know for a fact on a 120GB drive, you only actually
> get about 111GB storage, but I just can't seem to
> prove it via maths - even working on a 40GB drive I
> can't get it to work out (and I've done the maths to
> prove it before, too).

I think I answered my own question, at least in the case of Win XP and WIN ME - System restore! I checked my 20Gb disk, which never seemed to add up, but when I factored in about 12% for system restore, it all added up...

Lizard

Graham L
08-02-2004, 02:34 PM
And the 1.44MB is very simply defined as 1440*1024 (2880*512). IBM's "megabyte is 1000 * 1024 bytes.

There's an interesting paper by Markus Kuhn about computer units of size (http://www.cl.cam.ac.uk/users/mgk25/information-units.txt). Smart guy, the rest of his online stuff is interesting too.

Lizard
09-02-2004, 08:03 AM
> And the 1.44MB is very simply defined as 1440*1024
> (2880*512). IBM's "megabyte is 1000 * 1024 bytes.
>
> There's an interesting paper by Markus Kuhn about
> computer units of size (http://www.cl.cam.ac.uk/users/mgk25/information-u
> its.txt). Smart guy, the
> rest of his online stuff is interesting too.

Very interesting article. Makes you wonder how anyone in the computer industry can agree on anything. Then again, maybe that explains why Wintel PCs can be so unstable! :D

Lizard