There are two identical disks attached to SATA ports in the mother board. It is set up with a Windows Mirror. It is not RAID 5 but a "Mirror" what ever that means.
This "windows mirror" would make me suspect that the drives are perhaps declared "dynamic", not "basic" ones.
This dynamic disk notion was introduced in the microsoft systems since windows 2000 (or perhaps in some nt version) to make something like "software RAID" & LVM in Linux. It is still available, I think, but it wasn't really popular among system administrators, because it was incompatible with robust and approved tools they like to used. A disk failure can destroy an entire filesystem.
This dynamic disk system offered possibilities of "mirror" drives (something like RAID 1) or make a bigger disk space from more drives (like RAID 0). You can find more info on this, in your windows system help.
If so, I don't think parted could work on these drives. You have to look for any windows-specific tools. In such a case, you can't go back from dynamic to basic.
To check if the drives are really dynamic, you have to use the "disk management". The graphical representation of the drive space contains "Basic" or "Dynamic", perhaps stripped, spanned, ... .
A true RAID device appears usually there as one "basic" disk.
Please, look at the following link for info:
http://msdn.microsoft.com/en-us/library … s.85).aspx
In case of some motherboard-based RAID, Gedakc already replied above.
In this case, you need the motherboard manual to find details on the RAID setup. If you don't find anything on RAID support in the motherboard manual, it is possible that the mirror is configured by the operating system from 2 dynamic drives.
In any case, I would recommend a good backup of any important data on this system. The drives are perhaps old, the system isn't very easy to support, it is better to be on the safe side.
*** It is highly recommended to backup any important files before doing resize/move operations. ***