Just had a thought, is the partition 6gig or 6.3gig, its important which it is as if its 6.3 then it could be your bios that is causing the problem. Have a look in it to see if u can auto detect the drive.
There is no unallocated space because you've created a 120GB partition (of which you are using 6GB). Do a proper partioning of your HDD before you go complaining.