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swaz
23rd May 2010, 07:51 AM
Just put a 500GB HDD in my macbook and also my Mini and the available space on the mini was something like 498GB, once formatted the drive in the MB was only 465GB. What's up with that. I understand that you never get the full capacity of the drive, but losing 35GB isnt cool!
Exact same drive installed on both. MB running leopard and the mini running Snow leopard.

glacierdave
23rd May 2010, 07:58 AM
Snow Leopard calculates drive capacities using base 10, Leopard uses base 2. It's the same drive with the same capacity both times, just a different way of reporting it.

FWIW, Snow Leopard is probably on the right track as drive manufacturers have also gone to base 10.

JimWOz
23rd May 2010, 08:10 AM
...MB running leopard and the mini running Snow leopard.

Leopard, Tiger, Panther etc all calculate the disk space strictly correctly in terms of binary. 1KB = 1,024 bytes (2^10 bytes), 1MB = 1024 KB, 1GB = 1024 MB. But the 500GB disk actually has 500,000,000,000 bytes, (drive manufacturers have been doing this forever) which is only 1/(1.024)^3 = 0.931 x 500GB =465.66.

Snow Leopard uses the bastardized form. 1KB = 1000 bytes.

At least the numbers all appear to add up now....

swaz
23rd May 2010, 04:31 PM
Ah ok thanks.
Next question, where on earth does the 35ish GB go?

wullieb1
23rd May 2010, 06:01 PM
It doesn't go anywhere as it doesn't exist.

The 500GB is not an actual 500GB in the true sense of the words.

The 500GB stated on the drive will be 500,000,000,000 bytes where as a true 500 GB is 512,000,000,000 bytes.

JimWOz
23rd May 2010, 06:34 PM
...where as a true 500 GB is 512,000,000,000 bytes.

I make it 536,870,912,000 bytes actually. (1024^3 x 500) :cool1:

snark
23rd May 2010, 06:52 PM
The 500GB is not an actual 500GB in the true sense of the words.

The 500GB stated on the drive will be 500,000,000,000 bytes where as a true 500 GB is 512,000,000,000 bytes.

Strictly speaking, 500 gigabytes is always 500 x 10^9 (500 x 1,000,000,000) bytes. However, when it comes to data storage, most people are lazy and use the term "giga" interchangeably with the quantity 1024 x 1024 x 1024

There is another prefix "gibi" that means 2^30 (ie. 1024 x 1024 x 1024).

Binary prefix - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Gibi#IEC_standard_prefixes)

D_W_Y
25th May 2010, 05:44 PM
does anyone know if its possible to change how snow leapord reports it back to what it actually is?

glacierdave
25th May 2010, 06:45 PM
does anyone know if its possible to change how snow leapord reports it back to what it actually is?

There's no point.

It's exactly the same drive either way.

You can put exactly the same amount of data on it either way.

It's only the way drive space is reported that changed.

The down-site is that you can APPEAR to have lost drive space.

The bonus is that, with SL, it now reports drive capacities that'll actually come close to agreeing with the capacity printed on the drive itself.

Edit: I'd also add that "what it actually is" should be considered a very slippery term when talking about hard drives (and many other computer-related terms). The SL method is a whole lot closer to "what it actually is" than earlier OS X versions.

auspad
25th May 2010, 07:23 PM
could ths work the other way round? my uncle has a toshiba laptop and his 1TB hdd says 1200 and something gig instead

gehenna
25th May 2010, 07:52 PM
could ths work the other way round? my uncle has a toshiba laptop and his 1TB hdd says 1200 and something gig instead

nope, sounds like he has a 1.5TB drive.

auspad
6th June 2010, 12:48 PM
nope, sounds like he has a 1.5TB drive.

No it is, it's a western digital, and it says on the top 1tb and when you plug it into the computer it says 1tb western digital. The hdd capacity in 1263gb

NeoRicen
6th June 2010, 01:46 PM
does anyone know if its possible to change how snow leapord reports it back to what it actually is?
Snow Leopard is reporting what it actually is, it's just that no one else is.

gehenna
6th June 2010, 01:48 PM
No it is, it's a western digital, and it says on the top 1tb and when you plug it into the computer it says 1tb western digital. The hdd capacity in 1263gb

I highly doubt that is correct.

auspad
7th June 2010, 03:37 AM
I will get photos next time I go to Perth. Trust me I was just as suprised as you are.

BiRDBRAiN
7th June 2010, 07:24 AM
If I got a dollar for every time someone posted a "ZOMG WTFBBQ I lost MB's or GB's of data" I could buy a 1PB disk array and complain about losing 35TB of disk space! :D

DagrtheSnide
7th June 2010, 07:41 AM
Remember when a 17 inch CRT monitor was actually only about 15.5 inches viewable, same type of thing people complaining about being ripped off without investigating how the manufacturer made the measurements.