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When you buy a 250 GB hard disk there is not
actually 250 GB of space on it, it's only 232.9 GB
Likewise, when you buy a 500 GB hard disk, there is actually only 465 GB
space on it.
For a 1TB (1000 GB) disk, the actual capacity is only 931 GB
That's because all the disk manufacturers use a different calculation method than Windows uses.
The Windows method is mathematically accurate, the manufacturer's method is not.
So that's why your last two partitions are less than the other three.
If you add them all together it equals 232.9 - which is the maximum you can have on a 250 GB disk.
Edited by pip22, 09 March 2011 - 10:54 AM.