fdisk -l will list your partitions..
How do you have Redhat on C:\ ?? It should reside on its own partition with the possibility of more partitions, etc, like swap, /boot, and so on...
Do you have multiple hard drives as well? More details about your setup, I don't like guessing games and I'm sure others here don't either. How you explained to us with your setup is in a Windows world of view and doesn't help us at all.