How to: Add a new hard drive

It's no wonder that adding a new hard drive is a popular PC upgrade, what with all those MP3s, home videos, and applications eating up disk space. These days, relatively inexpensive hard drives regularly exceed 100GB of space, and they're getting bigger and faster all the time. Adding a new drive is one of the easiest and most efficient ways to clear out some elbowroom on your overcrowded PC. But before you install such a drive, you'll need to prepare yourself for the inside of your computer.

Before you start, you'll need to gather these elements:

New hard drive

Mounting rails and ribbon cable

Screwdriver

Floppy disk

Required attention span: 30 minutes (excluding backup time)

Follow these five steps...

Step 1

Select a new hard drive. Unless you really need to replace a poorly performing drive, it's easier to add a second drive. Either way, when choosing a new hard drive, look for both capacity--get the biggest one you can afford--and performance. You'll also need to choose between ATA and a SCSI drives. In general, we recommend a SCSI drive if you are adding a second hard drive, as SCSI performs better in multiple hard drive situations, though ATA drives can be cheaper. Drives with faster rotation speeds generally promise speedier performance (look for a spindle speed of 7,200 rpm), and you'll also need to make sure that the drive you choose fits an open drive bay on your PC. Hard drives come in 3.5-inch and 5.25-inch sizes; your PC's manual or technical specs should specify the size of your drive bay. Finally, make sure that you have any extras such as mounting rails and a ribbon cable that supports two drives.

Step 2

Prep your system. Back up your hard drive to removable media, such as a CD or a Zip disk. If you use Windows 95 or 98, make a bootable floppy disk using the Startup Disk tab in the Add/Remove Programs dialog box (Control Panel). From the tab, click Create Disk and follow the instructions. In Windows XP, insert a blank floppy, click Start > My Computer, then right-click the A: drive icon and click Format. Check "Create an MS-DOS startup disk," then click Start. Finally, go to the CMOS screen (as you boot up your computer, you can press a certain key to enter the CMOS setup--it varies by PC) and write down all of the information on the BIOS settings for your current hard drive. You may need this to configure the second drive.

Step 3

Get inside your computer. Turn off your PC, unplug it, and open the case. Next, ground yourself by touching any part of the metal case or wearing an antistatic grounding strap around your wrist--you want to avoid any kind of static electricity, which could fry your drive before you even start. Remove the cover from the case, and find the open drive bay. Slide the new drive into the bay or onto the mounting brackets.

Step 4

Make the connections. The ribbon cable runs from your controller to your hard drive. If there is no free connector on the cable, you have to buy a new one. Connect the ribbon cable connector to the 40-pin slot on the hard drive. The ribbon cable has a stripe on one side of it, indicating which side of the cable plugs into pin one (located closest to the power supply connector) on the hard drive. The power-supply cable has a connector on the end of it--usually four sockets encased in a small sheath of white plastic. Plug that into the connector on your hard drive.

Step 5

Configure the drive. If you keep your existing hard drive (master), you'll set the new one to be slave by setting the jumpers on the back of the hard drive according to your drive's manual (check this site for jumper settings on a variety of drives). Because your new hard drive is faster and bigger than your old one, you may want to set the new drive as the master and the old one as the slave. Once you've correctly set the jumpers, screw the drive firmly into place. Finally, close the case and boot your computer. Enter the CMOS settings again. Newer computers may automatically detect the new drive and set appropriate values, and various SCSI drive manufacturers have different methods for configuring and formatting your drive properly. Check your drive manual for specific instructions.