1. On the bottom of your Sony VGN-FW398Y laptop, find the hard drive door to access the hard drive.
2. Remove the Screws.
3. In this step, you will either need to pry out your Sony VGN-FW398Y hard drive caddy, or simply remove the door.
4. Once the Sony VGN-FW398Y hard drive is removed the laptop, you need to remove the hard drive caddy. There are usually four screws to remove from the caddy.
5. Simply Insert the new hard drive into the caddy. Place the screws back in. Install your new Sony VGN-FW398Y hard drive.