Sounds like your XP Install disk is an original version, and you re-install from that and then update to SP2 afterwards. It appears SATA was not supported in earlier Win XP. To get to use a SATA drive as a boot drive you have two options.
First is IF you have a floppy drive, you can put the necessary drivers to support SATA drives on a floppy. On every boot you can push the F6 key at the right moment and have it load the drivers from the floppy.
Second is you can make your own updated install disk with SP2 included on it. This is the process called "slipstreaming". You start by searching for the info on the net, including the Microsoft site. There are several good step-by-step instructions for this. They will tell you what software (free) you also will need to download. Following the instructions carefully, you basically copy your legit XP install disk to a new subdirectory in your hard drive, then download and run the SP2 updater that fixes all the files on that copy. Then you use the right software to create a bootable CD and copy to it all the updated stuff to create a new XP install disk with SP2 already included. You use this, then, as your new XP install disk to install to your SATA drive, and voila! Slipstreaming is completely legal if you are starting from your own legit older XP install disk. It takes carefully following the instructions, but it works. I've done it. Of course, you need a CD burner, but most people have them now.
By the way, among many other things, updating to SP2 also means you have support for "48-bit LBA", which is how you get to use hard drives over 127 GB in one volume.