750 gig drive but really 698 gig?

Beat Takeshi

Beat Takeshi

Two-Hip Shakur
I just got a 750 gig mybook and I went to format it and it says its a 698 capacity. What kind of bu11 sh1t is that?
 
hahaha.... True.
Each cluster can only be occupied by one file so if you have say 100 1k files on a drive with a 4K cluster size they'll actually take up 400k of space.

750GB as SI-System Giga-Bytes means 750*10^9 B = 750.000.000.000 bytes = 0.75TB

So to the OS it would be like 750 000 000 000 bytes(B) = 732.421.875 kB = 715.255 MB = 698 GB = 0.682 TB

The following is an example system with 4 400 GB disks. Remember that drive manufacturers state GB in 1000 * 1000 * 1000 bytes, not 1024 * 1024 * 1024 bytes.

4 x 400GB = 1600 GB (this is the raw capacity)
Minus Parity (1 disk capacity) = 1200 GB
Drive manufacturers quote GB in 1,000,000,000 bytes, so actual 1200 GB = 1144 GB
Minus 2% reserved for volume overhead (28GB) = 1116 GB
Minus 5% for snapshot (56GB) = 1060 GB (this is the usable capacity)
 
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its completley normal dude, the rest is partitioned for information or some crap like that, anyway its nothing to worry about it happend on any external hard drive, you are never gonna get the full 500gb or 750gb in your case
 
BASTIDS!!! So changing the cluster size won't do crap I guess. Oh well.
Thanks. Kwan, didn't know you were so technical. Now I know. :)
Ghetto Barry Green you are.
 
I never really paid attention to the numbers before. I guess since its multiplied so much this time I noticed. :P
 
It's a scam...I've been making a documentary on the whole deal of illegal, misrepresented hard drive capacities for the past four months. I've got a meeting on Wednesday with the Vice President of Seagate and I'm going to get this all figured out. Eventually my hopes are that they'll put the 'true' post-formatted disk capacity on all future packaging. It's either that or the end of democracy as we know it...

I'll let you guys know how the meeting goes...
 
It's been known for years that approximately 10% of a drive's listed capacity is unavailable for writing. Nothing new here.
 
It has to do with the way file systems are structured and counted. Imagine a bottle is listed as having a certain capacity, like 12 fluid ounces. And it's true - if you pour water, it'll fill up exactly 12 fluid ounces. But if you pour in sand, it will be - depending on the size of the grains of sand something LESS than 12 fluid ounces (because of all the spaces between the grains of sand). Now, has the bottle seller lied to you when he said the bottle capacity is 12 fluid ounces?
 
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