I'm not sure where to put this, but here it is.

Using a already formatted & partitioned HDD from a older non GPT ready (if you will) MB, I want to install Win7 64 bit using AHCI. The current O/S on that active partition is XP which I want to replace.
The other partitions (two) have data on them that I don't want to loose. (I do have it backed up).

What happens to the drive when I install Win7 in AHCI mode to the other non active partitions?