New Drive In XP
Sometimes when you purchase a new drive (sata or ide) and try to mount on an XP machine via a USB, nothing will appear under "my computer". This absence isn't necessarily a problem, it just means that your new drive must first be initialized using Windows Disk Management.
To access Disk Management go to Start>Control Panel>Administrative Tools>Computer Mangement... Inside of "Computer Managment", on the right side, you'll see the Disk Management option near the bottom. With your new drive plugged into the system, click on this option. The drive should appear on the right half at the bottom of the screen. Right-click on the drive and use the wizard to initialize the drive. After this step, the drive will now appear with some unformatted unpartitioned space to the right of the drive. Right click on this space (not the drive name) to create partitions and even a logical drive. After finishing these steps, the drive will appear and will be accessable under "My Computer."