Add a Second Hard Drive

Preparing for a New Hard Drive

First, determine whether the computer system has room for an additional hard drive. Following the instructions in your computer's operations manual, open the computer case and find the hard drive. (It will probably be about an inch high, three and a half inches wide, and about five or six inches long, with two connectors plugged into it.) If there is room above or below that hard drive for another device the same size, you probably have room for a second hard drive.

IDE or SATA?

Next, look at the cables attached to the existing drive. One will be a power connector and the other will be a data connector. The power connector routes to the computer's power supply and the data connector routes to the motherboard. If the data connector is wide (about two inches), this is an IDE drive, and you will need to get a second IDE drive. Also, check to see if there is available space to plug in a second drive on the same ribbon cable. If not, you will need to install a second ribbon cable in the second drive controller slot on the motherboard, assuming it's available. (The cable should come with the drive.)

If the data connector is small (less than an inch wide), you have a newer SATA (Serial Advanced Technology Attachment) drive, and will need to purchase another SATA drive. You should have plenty of space available on the motherboard to add another SATA drive, as most motherboards that support SATA have at least four SATA connectors.

Megabytes or Gigabytes?

The storage capacity of the Hard drives of yesteryear were measured in megabytes, and one megabyte (MB) is about one million characters. There was a time when hard drives cost about $10 per MB, and they were about the size of a small toaster.

Today, hard drives are much smaller and much cheaper. You can buy one gigabyte (1GB = 1000MB) of storage for under a buck, and they're just a little bigger than a calculator.

So live large! I recommend you go for at least 80GB, or larger if it fits your budget. But check your computer's manual to see if it can handle a monster drive before you buy.

Installing Your Hard Drive

If you are installing an IDE drive, on the same cable as the original drive, set the new drive's jumper (the small plastic connector on the set of pins by the data connection) to the Slave setting. If you're installing an IDE drive on a second ribbon cable, and it's the only device on that cable, use the Master setting. If you have a CDROM drive attached to the secondary IDE connector, make the new hard drive Master and the CDROM Slave, setting the jumpers on each device accordingly. The position of the pins for the Master or Slave setting may vary from one drive to another, so refer to the documention that came with the drive.

Most importantly, before you mount the drive in the computer, look on the printed circuit board on the bottom of the drive to find which pin of the data connection is pin 1. It will be labeled with either a "1" or a solid white triangle. This information may also be stamped into the drive case near the connector. The ribbon cable will have a speckled red edge, and this edge MUST correspond to Pin 1 on the data connector, or the computer will not recognize your new drive.

With a SATA drive, the process is much easier. Simply plug the power connector into the drive, and connect the drive to the motherboard SATA controller using the supplied SATA cable. (Both connectors are both keyed to prevent improper connection.) With SATA drives, there is no need to change jumper settings, though you may need to update your computer's BIOS if it can't see the drive.

External Drives

If messing with motherboards is not your style, you can get an external hard drive that connects easily to your computer with a USB cable. External drives are a bit more expensive, but the easy setup and the fact that it's portable make it a good choice for some. The Iomega 33xxx series and the Maxtor OneTouch get high marks from reviewers and users, but other manufacturers such as Seagate and Western Digital make good products as well. Look for a drive that supports a USB 2.0 connection, or the faster FireWire hookup if your system supports it

Copying Your Data

Chances are, your new drive will be larger and faster than the old drive. If so, you may want to copy the contents of the old drive to the new one, and keep the old drive as additional storage. You may also opt to leave just the operating system files on the old drive and keep all user data on the new one.

For help copying your old drive to the new drive, see my article Copying Old Hard Drive to New PC.