Danno
13-01-2006, 02:13 PM
Q. Why does my 80gb hard drive show only show as around 75gb once formatted even tho the BIOS reports 80gb? or Why does my 160gb hard drive show only show as around 150gb once formatted even tho the BIOS reports 160gb?
A. Below is a copy of an email from Seagate tech support explaining the missing space.
What seems to be missing space on the hard drive is actually the
difference between
the two numbering systems used in the computer industry.
Decimal vs. Binary
Most Hard drive manufacturers use DECIMAL numbers to show capacity:
(1 KB = 1,000 bytes)
(1 MB = 1,000,000 bytes)
(1 GB = 1,000,000,000 bytes)
Most Computers (BIOS) and Operating Systems use BINARY numbers to show
capacity:
(1 KB = 1024 bytes)
(1 MB = 1,048,576 bytes)
(1 GB = 1,073,741,824 bytes)
EXAMPLE:
Seagate's Model ... ST380021A ... total formatted capacity expressed in:
DECIMAL = 80 GB ...
The same drive will show up in Windows expressed in BINARY as
approximately:
BINARY = 74.5 GB.
Use this formula to convert the DECIMAL 80 GB to a BINARY number
800,000,000,000 ... divided by ... 1,073,741,824 = 74.5 GB
Your Operating System would show this 80 GB drive as a BINARY number
equaling 74.5 GB ... minus any space already used.
IN SUMMARY:
You are NOT missing any space on your Seagate hard drive.
Your Operating System is converting the DECIMAL number and displaying it
as
a BINARY NUMBER.
A. Below is a copy of an email from Seagate tech support explaining the missing space.
What seems to be missing space on the hard drive is actually the
difference between
the two numbering systems used in the computer industry.
Decimal vs. Binary
Most Hard drive manufacturers use DECIMAL numbers to show capacity:
(1 KB = 1,000 bytes)
(1 MB = 1,000,000 bytes)
(1 GB = 1,000,000,000 bytes)
Most Computers (BIOS) and Operating Systems use BINARY numbers to show
capacity:
(1 KB = 1024 bytes)
(1 MB = 1,048,576 bytes)
(1 GB = 1,073,741,824 bytes)
EXAMPLE:
Seagate's Model ... ST380021A ... total formatted capacity expressed in:
DECIMAL = 80 GB ...
The same drive will show up in Windows expressed in BINARY as
approximately:
BINARY = 74.5 GB.
Use this formula to convert the DECIMAL 80 GB to a BINARY number
800,000,000,000 ... divided by ... 1,073,741,824 = 74.5 GB
Your Operating System would show this 80 GB drive as a BINARY number
equaling 74.5 GB ... minus any space already used.
IN SUMMARY:
You are NOT missing any space on your Seagate hard drive.
Your Operating System is converting the DECIMAL number and displaying it
as
a BINARY NUMBER.