Capacity Settings (untins?)

Could someone tell me what units should i use for Capacity Settings? i mean, there is no information (even in the official documentation), on what units should i use for this setting? Bytes, Kilobytes, Megabytes, Gigabytes, Terabytes?

As I remember, you can use any of them. (Even down to kB range, if I am right)
So 8GB is equal to 8000MB (Actually it is 8196MB, to be accurate) or 8 000 000 kB.
But, as I remember, it will take any number, even if it is not the any power of 2…