Windows XP did not come with drivers for the motherboard’s SATA controller, so if you are installing the drive as a system drive (a drive where you expect to install the operating system), you have to follow a procedure to load a driver during the XP installation process.
Specifically, you have to have a floppy drive and a floppy disk with the driver on it, and during the XP installation process, there’s a point where you are prompted to press F6 on the keyboard to indicate that you will need to load that driver, then later on in the XP installation process, you will be prompted to load the driver.
Generally, the necessary driver is available from the PC manufacturer, the motherboard manufacturer, and the chipset or SATA controller manufacturer. A great many people have motherboards with Intel chipsets and therefore Intel SATA controllers, and it is possible though somewhat challenging given a complex website design, to get the appropriate “F6 driver” from Intel in a form appropriate to copying to a floppy disk.
If you are installing the drive as a data drive, in addition to the harddrive where XP is installed, things are much easier. You can download and install the SATA driver after booting up, and in fact the SATA controller driver is probably already installed, and XP will automatically install the drive and ask you to reboot, after which time, you will be able to initialize the drive and format it. (if, in Windows, you right-click on the Computer icon, and choose “Manage” from the right-click context menu, you will go to system management console, where you can access the Disk Management tools to do what you need to do, as far as formatting the drive.)
It is remotely possible that the SATA controllers/port you wish to use has been disabled in the BIOS, and you will need to enter the BIOS at bootup, and enable it. How you get into the BIOS varies by system; usually you press DEL or F2 or some other key during the powerup sequence prior to Windows loading.
That’s an exhaustive explanation, I know, but you said you were clueless. You will need a SATA cable for the data connection to the motherboard, and if your powersupply doesn’t have a SATA connecter, a SATA power adapter to attach to one of the powersupply’s MOLEX connnectors.