Hard Drive

[John Haughey]

I am recently having a problem with my hard drive. I
purchased a 120Gb hard drive and when I install it, the
full disk space allocated is nowhere near the 120Gb. I
have no Operating System or files on the drive, however,
when I check the capacity, it is 111Gb all together. I
know that when buying hard drives, especially 120Gb ones,
it will always be slightly shorter than it is suppose to
be but I am losing approximately 9Gb.

Can someone please help me because I feel that I might
have been ripped off.

Thanks for your time
John

 

[Pete Baker]

Hi John

You are not missing any space - although the drive manufacturer could be
clearer. For drive manufacturers 1,000,000,000 bytes = 1 Gb, whereas an OS
will regard 1,073,741,824 bytes as 1 Gb. (It's a decimal V binary thing)

The best way to see this is in XP. With XP installed, open My Computer,
select the appropriate
drive and right-click, select properties... beside 'capacity' you will see
the total number of bytes on your disk and to the right the number of
Gigabytes.

For example, on my 120 Gb drive I have 120,023,252,992 bytes... which is
also listed in disk properties as a capacity of 111 Gb.

The Hard Drive manufacturer refers to the 'bytes' total in my case as 120
Gb... and, in purely decimal terms, it is - 120,000,000,000 bytes.

The 111 Gb is what the operating system (XP in this case) 'sees'... because
the OS
calculates the storage in binary terms... 1024 bytes as 1 Kb, 1024 Kb as 1
Mb, and 1024 MB as 1 Gb.....

so in my case 120,023,252,992 / 1024 / 1024 / 1024 (that's bytes =>
Kilobytes => Megabytes => Gigabytes) is 111.78 Gigabytes as far as the
computer is concerned. (The drive capacity may only show the first 3
digits.)

Neither calculation of the disk size is 'wrong' ...... they are equivalent.

In your case, the drive capacity of 120,000,00,000
bytes (or close to that value) will be referred to by 'My Computer' as 111
Gb
after the above calculation.

Of course, by using the decimal definition drive manufacturers are only
obliged to provide 120,000,000,000 bytes when they claim a drive size of 120
Gb.

Hope that helps
Pete

 

[Guest]

Sorry,

Should be 120GB=120X1,000X1,000,000/1,048,576X1,024=111.76GB

Peter

----- Peter wrote: -----

Hi,

You said you have on OS installed, so where are you getting this figure 111GB for the HDD?

1 megabyte = 1,048,576 bytes
120GB=120X1,000X1,000,000/1,048,576X1,000=114.44GB
HDD manufacturer use 1 mb=1,000,000bytes for calculate Hdd volume.

You are not ripped any way.

Peter


----- John Haughey wrote: -----

I am recently having a problem with my hard drive. I
purchased a 120Gb hard drive and when I install it, the
full disk space allocated is nowhere near the 120Gb. I
have no Operating System or files on the drive, however,
when I check the capacity, it is 111Gb all together. I
know that when buying hard drives, especially 120Gb ones,
it will always be slightly shorter than it is suppose to
be but I am losing approximately 9Gb.

Can someone please help me because I feel that I might
have been ripped off.

Thanks for your time
John