On most new systems, make sure the jumper on the back is set on CS(cable select). After booting XP may not see the drive. If it doesnt shut the puter down and change the jumper to slave, then reboot. Install the drive next to the HD thats in the computer, hook the middle connector on the data cable to the new drive, and hook up a power connector. Windows should see the drive and you should be able to pull any data you want off. Usually windows will not see the OS on the second drive, but since it was bootable, You may get a window on startup asking you which Xp you want to boot to. Select theoriginal XP from the computer. When it boots you should be able to use explore to move data from the second to the first drive. If i was not going to keep the drive in the computer i would not even install the drive, just connect it up and transfer files, then shut down and remove the drive. Planning on keeping the drive in the puter? Save all the data and while in XP use control panel to reformat the drive. Then you have more space to put data just by making folders and moving the data to the folders.