How to Add a Second Internal Hard Drive - dummies

How to Add a Second Internal Hard Drive

By Mark L. Chambers

For most current PC owners, the easiest method of adding more hard drive space is to add a second hard drive to their systems. There are three very good reasons for this:

  • No backup is required. Of course, you should be backing up your current hard drive anyway. Adding a second drive eliminates the setup that you have to perform if you upgrade your current drive because you don’t have to restore the current contents of your old drive to the new drive.

  • Most PCs have at least one open drive bay. Unless your computer is already stuffed to the gills, you should have enough room to add a second hard drive. If it is stuffed to the gills, you either have to upgrade the current drive or add an external FireWire, eSATA (external SATA), Thunderbolt, or USB 2.0/3.0 drive.

  • It’s like . . . well . . . more for less. Rather than replace an existing 500GB drive with a 1TB drive — and end up with only 500GB more room — leave the original drive as is and add that second drive, resulting in the full 1TB that you paid for. (Remember: You will eventually use that space.)

Are you girded and ready for battle? Because there are actually more steps involved in the installation of an EIDE drive. Follow this procedure to add a second internal EIDE hard drive to your current system:

  1. Cover your work surface with several sheets of newspaper.

  2. Turn off your PC, unplug it, and place it on top of the newspaper.

  3. Remove the case screws and slide off the case, putting the screws aside in a glass or wooden bowl or cup.

    If you’re unsure how to remove your PC’s case, check the manual that accompanied your computer.

  4. Touch the metal chassis of the computer to dissipate any static electricity.

  5. Verify the jumper settings on the back of your original drive. If necessary, change the existing drive to multiple drives, master unit (or just master) by moving the jumper to the indicated pins.

    Remember, if you’re installing a SATA drive, you won’t need to worry about jumpers! Just skip to Step 7.


    Jumpers are the tiny plastic and metal shunts that you use to configure hard drives and CD/DVD drives.


    Your jumper configuration is probably different from the one shown. Most EIDE hard drive manufacturers now print the jumper settings on the tops of hard drives. If the settings aren’t printed on the drive, you can refer to the drive’s manual or visit the manufacturer’s website and look up the settings there.

    If all this seems a little exotic, the terms really aren’t risqué; master means primary (and if you have at least one drive, there must be a master device), and slave means secondary. Other than that, the devices are treated the same way by your PC.

  6. Set the jumpers on the back of the new drive for multiple drives, slave unit (often listed as just slave).

  7. If your new drive needs a drive cage to fit into the desired bay, use the screws supplied by the drive manufacturer to attach the cage rails to both sides of your drive.

  8. Slide the drive into the selected bay from the front (or inside) of the case, and make sure that the end with the connectors goes in first and that the exposed circuitry of the drive is on the bottom.

  9. Slide the hard drive back and forth in the drive bay until the screw holes in the side of the bay are aligned with the screw holes on the side of the drive (or on the drive cage rails).

  10. Tighten down the drive to the side of the bay with the screws that came with the drive (or your cage kit).


  11. Choose an unused power connector and plug it in, and make sure that the connector is firmly seated.

    Joyfully, there’s only one way to connect a power cable to a hard drive — the right way.


  12. Plug the other connector from the hard drive cable into the back of the drive and make sure that the cable is firmly seated.

    Note that both EIDE hard drives use the same cable, so you might need to unplug the original drive from the cable and switch connectors. Don’t worry: It doesn’t matter which connector goes to which drive as long as the jumpers are correctly set. (Multiple SATA drives do not use the same cable, as each SATA drive is individually connected to the motherboard.)

    Check for a blocked hole in the cable connector, which should align with a missing pin on the drive’s connector. This alignment trick, called keying, helps ensure that you’re installing the cable right side up. However, don’t panic if the cable isn’t keyed: Remember that the wire with the red or black marking on the cable is always Wire 1 and that it should align with Pin 1 on the drive’s connector.


  13. Replace the cover on your PC and tighten its screws.

  14. Plug your PC back in and turn it on.

  15. Run the drive formatting utility that accompanied your new drive to prepare it for use.