Velocity Reviews - 30 gig drive only 25 after format??

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30 gig drive only 25 after format??

my original question was: why did you advertise
a product with a 30 gig hard drive and sent one
with only 25 gig. here is his response. is he on
the level?? i don't see formatting taking up 5 gig.
perhaps i am wrong. please. i need your responses.
be as concise as possible. thanks in advance.

Dear Dell Customer,

Dell's e-mail software interprets your
message as a request for information
about a discrepancy in reported hard
drive size. This response document offers
information about that issue.

Binary vs. Decimal Numbering Systems
=============================
Manufacturers and marketers of computer
hard drives report the raw storage capacity
of the drives before they are formatted and
in decimal numbers. A decimal megabyte is
1,000,000 bytes. Windows, however, reports
the capacity of the hard drive after formatting
and in binary numbers. A binary megabyte is
1,073,741,824 bytes. Clearly, there are more
decimal megabytes in an unformatted drive then
binary megabytes in a formatted one.
The result is that the same drive may be described
as having a capacity of 80 MB or about 75 MB
depending on which numbering system is used and
whether the capacity is calculated before or after
low-level and high-level formatting.

The Effect of Cluster Size
===============================
Other factors also reduce the available capacity
of a formatted hard drive. Cluster size is one
factor. A cluster is the smallest storage unit
available on a drive. In general, the larger
the drive the larger the cluster size. This means
that a small text file of 100 bytes will be stored
in a very large cluster of 32,000 or 64,000 bytes,
and nothing else can be stored that cluster.
Most hard drive formatting results in significant
amounts of unusable storage capacity. NTFS clusters
are smaller than FAT32 clusters. You can use smaller
clusters if you divide a large physical drive into
several smaller logical drives. Most hard drive
utilities that increase available space do so by
compressing files and taking advantage of empty
clusters space. Dell Technical Support does not
recommend using compression utilities because they
are all somewhat unsafe for your data.

Low-level Format Reserve Sectors
=============================
Reserve sectors are another factor. It is
impossible to manufacture millions of perfectly
flawless high-capacity drive platters. All platters
have some flaws. Manufacturers reserve a certain
amount of raw hard drive space to swap for damaged
sectors that are locked out during factory low-level
formatting, and the size of this reserved space is
proprietary information. This means that a drive
labeled "80 GB" is only that large in decimal numbers,
before reserve sectors are taken, before low-level
formatting, and before high-level formatting.

Very Large Drive Size Discrepancies
=============================
If your 80 GB drive has only 32 GB of available
storage, you are dealing with an operating system
and file system limit, not a physical limit.

All current Dell computers are shipped with the NTFS
file system and either Windows XP or Windows 2000.

It is easy to change the file system to FAT32 in
Windows XP. Some customers MUST change to FAT32
so that an important legacy program will run under
Windows XP. However the largest FAT32 partition that
Windows XP can recognize is 32 GB. This limit is part
of the design of Windows XP, and Microsoft has no plans
to change it.

If you are adding a hard drive larger than 137 GB you
may need a third-party controller card or overlay
software to allow you to access the full capacity of
the drive. To learn more about this limit, enter the
words "138 GB limit" in any major search site.