To avoid this issue next time why not use the drivers and nlite and create a Windows CD that you can use. So that way you dont have to give the PC to your friend if you ever have to isntall Windows again.
I have this issue as well. My SATA drivers are not recognized by XP. Only by Vista. So i have to go in and add my sATA drivers to every Windows Disc i want to use. It is a pain but in the end when i have to re-install it is worth it. Just a tip i thought i might share.