Preparation

• Shut down the computer completely and unplug it from the power source. Remove the external case from the computer and set it aside. Touch a metal part of the computer before touching the drives to discharge any built-up static electricity.
  Look inside the computer and locate the hard drive. Most hard drives are rectangular in shape and about a half inch thick, and they should be screwed into a partitioned section of the computer called the drive bay. Hard drives are also easy to recognize by the wide, flat cables, called the IDE cables, which are plugged into them.
  Open the packaging for the new hard drive and get everything out. For the next step, you will need the new hard drive, the documentation from the drive manufacturer and the jumper. The jumper is a very small piece of plastic with several short pins protruding from it; its purpose is to designate the hard drive as either the main drive or the slave drive.
  Look through the documentation for a diagram that shows where you should place the jumper to designate the drive as a main drive or slave drive, then place the jumper in the position you desire. If you are not sure whether you want to set the new drive as the master or slave, choose to set it as the slave drive.
  
  

Installing and Connecting

• Slide the new hard drive into an empty slot in the drive bay with the IDE input jack facing out. If possible, leave some space between the new hard drive and the old one to maintain better ventilation. Screw the new drive into place using the four small screws that came in the drive packaging.
  Now it is time to connect the IDE cable, which is the flat, wide cable connecting your old hard drive and the motherboard. You can use the cable that is already in your computer, or you can use the one that came with your new hard drive.
  Look at the cable; you will see plugs at both ends, plus one plug located a few inches from one end. The plug farthest from the middle plug should go into the IDE output jack on the motherboard. One side of the IDE cable should be colored red; make sure this side lines up with the pin labeled as number one on the motherboard jack. Next, connect the middle plug to the IDE jack on the back of your slave drive, again making sure that the red side is aligned with the number one pin. Finally, connect the last plug to the master hard drive. Again, be sure the red side is lined up with the number one pin.
  
  

Finishing Steps

• Use the spare power supply cable that came with your new hard drive to connect it to your computer's power supply. Just look at the existing power supply connection on your old hard drive to see where and how to plug it in.
  Double-check all of your plug connections and make sure your screws are all tightened. Check around inside the computer to make sure you haven't left any tools or packaging inside. If it looks like it needs it, clear dust out of the inside of your computer using a compressed air dusting canister.
  Replace the metal case cover on your computer, reconnect the power supply and boot it up. Your new hard drive is installed and ready to use.