Real size of hard drives

[dashogun]

Is there a way to determine the correct number of GB that a hard drive can hold?

A 60GB hdd I have for my laptop says 55.7 in My Computer
500GB displays 465
120GB displays 111

Is this just to make the hard drive look better as 500-465GB is a lot. Or is it multiplied something different than 10.

 

[turtile]

Hard drive manufacturers use GB as in 1 billion bytes (decimal). But data is saved in Binary. So the the actual size of a GB is 2^30 which equals 1024MB instead of 1000MB (10^3).

 

[TheMajor]

Windows is making a mistake here (and most other software).

Windows measures in "GiB" (GibiByte) but it uses the term "GB" (GigaByte).

The hard disk manufacturers are correctly measuring and using "GB". It would be easier if the hard disk manufacturers used "GiB" as well, or if at least Windows wouldn't use the wrong terminology.

 

[networkgeek]

also you have to take into account the partition table as well. it takes a certain percentage of a drive for the formatting

 

[C0RR0SIVE]

Some drives have less, some have more due to bad sectors and the such, my maxtor drivers, where always extremly close to what they claimed, no more than 2gb off, but my 200gb drive is about 20 off...

 

[peterhuang913]

To get the display size from the advertised size: [advertised] * 0.931322575 = [windows display]

 

[Apokalipse]

Hard drive manufacturers use GB as in 1 billion bytes (decimal). But data is saved in Binary. So the the actual size of a GB is 2^30 which equals 1024MB instead of 1000MB (10^3).

spot on.

1GB = 2^30 bytes, or 1024x1024x1024 bytes = 1073741824 bytes

1000000000/1073741824 = 0.931322574615478515625

i.e. the actual capacity of a drive (in gigabytes) is 93.1322574615478515625% of its rated capacity.