than one Hard drive
more than one hard drive is installed on a computer system, each
drive competes for control of the computer. To allow both drives
to work in harmony on the same computer system, the controlling
(or startup) drive is designated the master drive and the other
drive is designated the slave drive. You can change this designation.
The following procedure applies to any PC-compatible computer.
1. Decide which hard drive will be the startup (master) drive. If
this drive was the startup drive previously, or if it's a new hard
drive, then the master drive designation will already be set.
2. To change the designation of a new drive to be a slave drive,
skip to step 4.
3. To change the designation of an existing drive to be a slave
drive: Turn off the computer, unplug the power cord, remove the
drive from its drive bay, and disconnect the drive from its power
cord and ribbon cable.
4. Check the hard drive documentation or the label on the drive
itself for master/slave jumper settings.
5. Find the jumpers on the circuit board of the drive. Jumpers are
plastic plugs with metal sleeves that form a circuit between a pair
of pins. Jumper locations are labeled on the board with a J followed
by a number (such as J20).
6. Use tweezers or very small pliers to remove or reposition the
jumpers to the configuration shown in the documentation or on the
Jumpers are very small and easy to lose. Hold your hand over the
jumper while removing it to keep it from jumping too far.
Store jumpers in a small plastic bag for future use.
Always disconnect the power cable from the computer before handling
the drive to prevent electrical shock.
Always ground yourself and your tools by touching a safe metal surface
(such as the computer cover or frame) before handling the hard drive
to prevent damage to the electrical components.
Avoid touching the pins with the tweezers or pliers to keep from
bending the pins.