It's not a problem, it's just two different scales. One uses giga
bytes and the other is giga
bits. I forget the exact details, sorry. It's annoying, but because of the difference in size you won't be able to "get the space back." My 80GB hard drive is actually only 74.5GB.
I did a Google search and thought that
these people may be able to help you more and explain it better.