I'm quite sure XP doesn't support AHCI drivers, but I'd wait for someone else to confirm that for you. I couldn't get AHCI to work properly even in W7 64 - always gave me BSODs. It's a shame really because my optical drives ran a lot faster in AHCI then IDE. Anyone else have a solution?

Got my EP45-Extreme yesterday - nice load of copper all over it, and some nice little features like NB temp! It is missing 2 sata ports compared to the UD3P and the bios doen't offer to save profiles to HDD unless you use the very latest F9d. The only huge pain is the fact the board vdroops by a huge 0.1v, so I'm heading into town shortly to get bits for a vmod.