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Halcyon

macrumors 6502
Original poster
Sep 21, 2006
335
0
Got my new 20" C2D iMac with a 320 GB hard disk...but when I check its capacity it says that it is about 297 GB and that 10 GB are already in used (system and few factory installed software).

Where are the other 23 GB of disk space?
 
Basically, when they say 320 GB they mean, 320,000,000,000 bytes...

When in reality, 320 GB is actually 343,597,383,680 bytes.

So if you convert 320,000,000,000 bytes into gigabytes, using the actual 1024 bytes per KB, 1024 KB per MB and 1024 MB per GB, you get 298.02 GB.

This is an industry standard way of representing hard drive storage...no matter how corrupt it seems.
 
Apple used to have that explanation around, now they just say "1GB is eqaul to x, formatted capacity may be less"
 
This is an industry standard way of representing hard drive storage...no matter how corrupt it seems.

It's not really corrupt, but a little sneaky. They did say 320GB, NOT 320GiB.

Wikipedia says:
GB = Gigabyte, GiB = Gibibyte (a "true" gigabyte")
1 Gigabyte = 1000 Megabytes = 1000000 kilobytes = etc
1 Gibibyte = 1024 Megabytes = etc

Apple dictionary says:
1 Gigabyte = 1024 Megabytes

So uh... I think the GiB notation was introduced to avoid confusion between 1000 and 1024 xs to a y, but instead just increased confusion. :eek:

Now if someone says "I have 1GB", it can mean either. Do flash drives use TRUE gigabytes (ie. GiB)? I'd imagine they would, as RAM and flash memory increases by powers of 2.
 
Actually, the stated capacity of a hard disk drive by manufacturers is the "unformatted" capacity of that disk. Formatting the disk into sectors reduces the effective capacity of the drive, because of the small gaps required between each sector. Full track blocking (one sector per track) is almost never used these days. Hard disks are composed of cylinders (the number of platters) and tracks (like the tracks on a vinyl LP only they are concentric) and, finally, sectors..

A gigabyte is 1024 x 1024 x 1024 bytes, or 1,073,741,824 bytes. So a 320GB disk is actually 343,597,383,680 bytes.

The reduction in capacity is simply, once again, the result of formatting.
 
It's not really corrupt, but a little sneaky. They did say 320GB, NOT 320GiB.

They note, "1GB = 1 billion bytes; actual formatted capacity less."

They just don't tell you that "actual formatted capacity less" means about 7% less.
 
They note, "1GB = 1 billion bytes; actual formatted capacity less."

They just don't tell you that "actual formatted capacity less" means about 7% less.

Not really, as noted above 320 x 1024 x 1024 x 1024 =343 "GB"

Since 320 is the nice round marketing number given that everyone uses, it is evident they are using the 1000 base method of figuring size.

This means, as far as the computer is concerned, the capacity is 298 GB using 1024.

Therefore, 297 is only losing 1GB for formatting.
 
Was there a successful lawsuit against Seagate for doing just that? Simple because the industry has a standard formula for calculating a hard drive's size and not doing that was considered false advertising? I wonder how much money I could get from Apple now?
 
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