XP fresh install

[w-r-g]

I put a new box together for a friend and put XP on and did not notice when I did that it was drive H instead of C ... everything works but how do I make drive H drive C? C,D,E,F are named removable drives in explorer. I had to turn ACHI or whatever on in Bios to get it to see the HDD and I made a small partition for the OS and just slapped XP on and only now I notice it is H instead of C. I assume I need to do away with drive C in bios somehow but what is the correct procedure here? Thanks

 

[KSoD]

You can not just make Drive H:\ Drive C:\. It would require a format and reinstall of the OS.