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Showing posts from August, 2007

SI Prefixes and Prefixes for Binary Multiples

A flaming article on Macenstein about the use of GB in describing hard disk sizes and the resultant frenzy at Digg shows the lack of understanding of standards amongst most people. This post is to clear the air. The computer world (especially memory manufacturers and software developers) have "always" used the prefixes kilo to represent 2 10 , mega to represent 2 20 , and so on. However hard disk drive (HDD) manufacturers use kilo to represent 10 3 , mega to represent 10 6 , and so on. The article claims that this misleading advertising by the HDD manufactures since one purchases a 1 GB HDD expecting (2 10 ) 3 bytes (1 073 741 824 bytes) but only gets 10 9 bytes (1 000 000 000 bytes). Most operating systems uses powers-of-2 for the prefixes and will report that HDD as being 0.931322575 GB (from 1 000 000 000 / 1024 / 1024 / 1024). This is being viewed as HDD manufacturers over-reporting HDD sizes by more than 7%. So what is going on and who is "right"? T