Have you activated it?
I bought a new 200gb HDD to increase all around free space, mainly for edit cuts for my movie. I put it in the secondary slave position, (Primary 1 and 2 already have HDD in them. One is a 40gb the other is a 150gb) and turned on my PC.
At the boot up screen, It read all the drives except the new 200. It read it out as 'None', but in windows it was an actual drive, just with 31.4gb free.
I right clicked on the drive and went to reformat, thinking that would solve the problem but in the capacity drop down menu it still said 31.4gb.
I have refrained from reformatting do to fear that it will get stuck at 31.4gb.