WD Elements 10TB shows as 9.09 TB

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1

Hello, I recently purchased a WD Elements 10TB from Amazon but when I plugged it in it has shown as 9.09TB (10 000 343 912 448 B).

Is there something wrong with the drive or are WD using the definition of 1 TB = 1000 GB, if it is the latter I will be quite annoyed indeed.

2

in the real world …

1 TB = 931 GB … or … 0.909 TB

All Manufacturers (WD, Seagate, Toshiba, etc etc) and Advertising use Base 10 mathematics

Computers and Operating Systems use Base 2 (Binary) mathematics

Plenty of info and explanation can be found regarding the difference in advertised capacity versus real capacity.

3

I was worrying that that would be the case. Whatever ■■■■■ brought in the change in definition from 1024 bytes to each KB has ■■■■■■ us all over. All other drives ive bought have used the correct definition so maybe this is a new stage in things.

4

It’s not new, been happening for a long time… ever since i can remember buying my first hard drive probably 20 years ago.

Basically the reasoning is … Since consumers don’t think in base 2 mathematics, manufacturers decided to rate most drive capacities based on the standard base 10 numbers we are all familiar with.

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5

This is how it has always been.

6

With SSDs, the actual physical capacity tends to be a true base-2 multiple, so a 1TB drive is actually 1024 GB of NAND, or 2^40 bytes, on the inside, but it only advertises 1000GB (10^12 bytes) because it’s over provisioned.

The extra space is used as spare sectors to improve lifetimes. The controller handles this as part of its wear-leveling job. Not all drives use the same amount of spares. So you can see both 500 and 480 GB drives. Both use 512GB of NAND, but the 480 has an extra 20GB of spare space.

Manufacturing memory chips in anything other than a base-2 size is not worth the trouble, but mechanical drives can be whatever size is needed.

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