only 929.5gbs in time capsule. Where did it all go?

[iCantwait]

I was checking out time capsule on apple.com and in the screen shot it only had xxxgb of 929.5 gb Tcapsule can't use that many gbs in formatting

[samh004]

That's about right for a 1TB disc. Someone else better at numbers can explain the difference between 1000 and 1024.

[thefunkymunky]

Its a hard drive. This happens with all hard drives. Has done for years.

[sammich]

okay, short and simple, 1 "terabyte" hdd = 1000 000 000 000 = 10 ^12 bytes
1 terabyte = 1024 * 1024 * 1024 * 1024 = 1024 ^ 4 bytes.

10^12 / 1024^4 = 931.32. Get it?

You can blame the hard drive industry for this numerical confusion.

[samh004]

okay, short and simple, 1 "terabyte" hdd = 1000 000 000 000 = 10 ^12 bytes
1 terabyte = 1024 * 1024 * 1024 * 1024 = 1024 ^ 4 bytes.

10^12 / 1024^4 = 931.32. Get it?

You can blame the hard drive industry for this numerical confusion.

I knew someone would explain things, I just didn't realise he'd live in a toaster...

[iCantwait]

so how come my 1gb stik holds 999.8mb? amd not 931.32mb?

[DNH]

okay, short and simple, 1 "terabyte" hdd = 1000 000 000 000 = 10 ^12 bytes
1 terabyte = 1024 * 1024 * 1024 * 1024 = 1024 ^ 4 bytes.

10^12 / 1024^4 = 931.32. Get it?

You can blame the hard drive industry for this numerical confusion.

Not to be picky, but your math is slightly incorrect.

1 gigabyte = 1024^3 bytes
1 terabyte (hdd) = 10^12 bytes

10^12 / 1024^3 = 931.32 GB

--

Regarding the USB stick, it may be that the stick holds a true gigabyte (1024^3 bytes).

Using the same convention, you might expect the following true capacity:
1 megabyte = 1024^2 bytes
1 gigabyte (stick) = 10^9 bytes

10^9 / 1024^2 = 953.67 MB


And yes, it took something this silly to draw me into posting for the first time in a looooong while.

[sammich]

Thanks DNH, as usual when it comes to maths I assume that if it looks almost right, it's close enough:p.

Regarding the flash drives, it may vary from manufacturer to manufacturer, some may use the 'true' mega/gigabyte storage capacities. Maybe it's the price of the OEM flash chips or the size that depends on how much space they have. Eg: my '512 meg' sony MS Duo only has about 470 megs.

One last thing: for extremely high end devices (ie SSD's and 10k+ rpm hard drives) manufacturers use the true values. ie the 64 gig SSD drive in the MBA actually is 64 gigs (64 * 1024 ^ 3 bytes).