Hardware Reference
In-Depth Information
Figure 7.7. PATA (IDE) drive jumpers for most drives.
The master jumper indicates that the drive is a master or a slave. Some drives also require a slave
present jumper, which is used only in a dual-drive setup and then installed only on the master drive,
which is somewhat confusing. This jumper tells the master that a slave drive is attached. With many
PATA drives, the master jumper is optional and can be left off. Installing this jumper doesn't hurt in
these cases and can eliminate confusion; I recommend that you install the jumpers listed here.
Note
Some drives have these jumpers on the drive circuit board on the bottom of the drive, and as
such they might not be visible on the rear.
To eliminate confusion over master/slave settings, most newer systems now use the cable select
option. This involves two things. The first is having a special PATA cable that has all the wires
except pin 28 running from the motherboard connector to both drive connectors. Pin 28 is used for
cable select and is connected to one of the drive connectors (labeled master) and not to the other
(labeled slave). Both drives are then configured in cable select mode via the CS jumper on each
drive.
With cable select, the drive that receives signals on pin 28 automatically becomes the master, and the
