I just bought a 320 GB Western Digital hard drive that I will be using as external storage. After installing the drive in my external bay, I plugged it in and used the formatting tools to make two partitions, 20GB and 300GB respectively. But, once I completed the process this is what I got:



As you can see, there is approximately 20 GB of space missing. I checked the drive using the software tools that came with the drive and got this result:



So the software is reporting that the drives were partitioned how I wanted.

(My local drive (partitions C,D & E) is a 160GB in size and I just noticed that appriximately 32 GB of space is missing from that as well.)

How did this happen?
How do I get my external drive to partition at 20GB and 300GB?

HI PC love & hate,

There is no space missing.
320gb doesn't actually equal 320gb...it's just a marketing thing unfortunately
It's actually 320000000 bytes...which equals around 300gb, which is what you have available. They just truncate the number and add it to the label.

Ok, I remember reading about that. But I still have some questions:
Shouldn't the smaller drive loose less space the larger one?
Why does the software tool report the correct size for the partitions while windows does not?
There is still the 21.06 GB (last block in disk 0) of unallocated space that remains unaccounted for. Where did that come from?

Because Windows represents 1GB as 1024mb, when iin reality should be 1000mb