160Gb drive while only 148GB capacity?

Question

Level 1

8 points

160Gb drive while only 148GB capacity?

I purchesed a new macbook with a 160 internal harddrive, and only after 2 days of use i have 125Gb avaiable. I have read that the system takes up alot of space and so forth, but the Macbook says that the capacity of the whole drive is only 148 GB. Is this normal?

Macbook 2.4 Ghz White 2GB Ram, Mac OS X (10.5.3), Early 2008 Model

Posted on Jul 2, 2008 7:46 AM

Reply

Answer 1

varjak paw

Level 10

182,668 points

Jul 2, 2008 8:42 AM in response to c.swain

Yes, it's normal. This is caused by a difference in how different entities define a 'GB'. All drive and media manufacturers quote capacity using 1,000 bytes per kilobyte while other entities, particularly in computer operating systems, use 1024 bytes per kilobyte (there's a new term that has been proposed for the 1024 usage to clear up the confusion, but no one uses it).

* 1,000,000,000 = 1,000x1,000x1,000 is used by hard drive and media manufacturers.
* 1,073,741,824 = 1,024x1,024x1,024 is used by the Finder and Apple's utilities.

Doing the math:

160 x 1,000,000,000 / 1,073,741,824 = 149 'GB'

Including formatting overhead, your hard drive will indeed have an effective capacity of about 148 GB.

Regards.

Reply

Answer 2

c.swain Author

Level 1

8 points

Jul 2, 2008 9:05 AM in response to varjak paw

Wow! Thank you for the detailed answer. I never knew about that. Thank you for replying so quickly as well

Reply