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Symptoms:
Why is the capacity of my flash memory card (as reported by many operating systems)
different than the capacity that is listed on its label?
Cause:
The operating system, when reading the size of the card, reports a slightly different capacity than
what is listed on the card’s label
Solution:
Definitions of a Megabyte:
1) Operating Systems commonly define a Megabyte (MB) as: 2 to the 20th power (1,024KB--
Kilobytes).
2) DiskDrive and Flash Memory Card Manufacturers commonly define a MB as one million bytes
(exactly 1,000,000 bytes).
Unformatted (Capacity)
Also known as drive byte capacity before formatting. The Maximum capacity of disk drive before
formatting equals
[ (# Cylinders) X (# Heads) X (# Sectors) X (# Bytes per Track) ]
Example:
64MB CompactFlash Card consists of:
490 Cylinders
8 Heads
32 Sectors
512 Bytes per Track
This equates to: [ (490) X (8) X (32) X (512) ] = 64,225,280
Unformatted Capacity: 64,225,280 bytes
Formatted Capacity: 63,934,464 bytes (User Data)
Cause:
Disk Drive Companies such as SanDisk define 1 MEGABYTE as 1,000,000 BYTES. Operating
Systems define 1 MEGABYTE as 1,048,576 BYTES (1024K X 1024K or 2 to the 20th power).
Example:
SanDisk 64MB CompactFlash Card being read by Microsoft Operating System.
SanDisk Total Formatted Capacity divided by 1 MB (as defined by the Operating System)
equates to the following: 63,934,464 BYTES / 1,048,576 BYTES = 60,972,656 BYTES, 60.9MB
displayed by OS.
Medyo may pagkamath at technicality dito. Just do the computations above and you'll get it easily. Sa mga naranasan ko, depende kung ano ang OS na nagformat ng MC mo and what is your MC, so interdependent ang dalawa to come out of what the result is. I'll try to explain later kung pano kompyutin ang 1GB, 2GB, 4GB, 8GB, 16GB at 32GB
Why is the capacity of my flash memory card (as reported by many operating systems)
different than the capacity that is listed on its label?
Cause:
The operating system, when reading the size of the card, reports a slightly different capacity than
what is listed on the card’s label
Solution:
Definitions of a Megabyte:
1) Operating Systems commonly define a Megabyte (MB) as: 2 to the 20th power (1,024KB--
Kilobytes).
2) DiskDrive and Flash Memory Card Manufacturers commonly define a MB as one million bytes
(exactly 1,000,000 bytes).
Unformatted (Capacity)
Also known as drive byte capacity before formatting. The Maximum capacity of disk drive before
formatting equals
[ (# Cylinders) X (# Heads) X (# Sectors) X (# Bytes per Track) ]
Example:
64MB CompactFlash Card consists of:
490 Cylinders
8 Heads
32 Sectors
512 Bytes per Track
This equates to: [ (490) X (8) X (32) X (512) ] = 64,225,280
Unformatted Capacity: 64,225,280 bytes
Formatted Capacity: 63,934,464 bytes (User Data)
Cause:
Disk Drive Companies such as SanDisk define 1 MEGABYTE as 1,000,000 BYTES. Operating
Systems define 1 MEGABYTE as 1,048,576 BYTES (1024K X 1024K or 2 to the 20th power).
Example:
SanDisk 64MB CompactFlash Card being read by Microsoft Operating System.
SanDisk Total Formatted Capacity divided by 1 MB (as defined by the Operating System)
equates to the following: 63,934,464 BYTES / 1,048,576 BYTES = 60,972,656 BYTES, 60.9MB
displayed by OS.
Medyo may pagkamath at technicality dito. Just do the computations above and you'll get it easily. Sa mga naranasan ko, depende kung ano ang OS na nagformat ng MC mo and what is your MC, so interdependent ang dalawa to come out of what the result is. I'll try to explain later kung pano kompyutin ang 1GB, 2GB, 4GB, 8GB, 16GB at 32GB
. Wala kasi magawa sa workplace. 
Anyways, ayan pinakita ko na kung ano yung lalabas na capacity ng MC pag nabili niyo. Iba talaga ang original capacity ng MC sa loob ng box at sa nasa label nito.
for the info share..
tnx po sa info....
