IBM IntelliStation M Pro Type 6868 User Manual page 100

Power and signal cables
Your computer uses cables to connect integrated drive electronics (IDE) and
SCSI drives to the power supply and system board. The following cables
are provided:
Four-wire power cables connect most drives to the power supply. At the
end of these cables are plastic connectors that attach to different drives;
these connectors vary in size. Also, certain power cables attach to the
system board.
Flat signal cables for connecting IDE and diskette drives to the system
board; signal cables are sometimes called ribbon cables. There are two
sizes of ribbon signal cables that come with your computer:
– The wider IDE signal cable has three connectors. One of these
connectors is attached to the CD-ROM drive, one is a spare, and
the third attaches to the primary IDE connector on the system
board.
– The narrower signal cable has two connectors for attaching the
diskette drive to the diskette-drive connector on the system board.
– If your computer is equipped with an internal Ultra-2 SCSI hard
disk drive, an Ultra-2 ribbon cable connects the drive to the
Adaptec 2940U2B SCSI adapter. This cable also has additional
connectors for attaching more internal SCSI devices.
Note: To locate connectors on the system board, see "Locating system
board components" on page 69. Following are some important
points to remember when connecting power and signal cables to
internal drives:
For computers with preinstalled software, more information on
connecting SCSI devices is available by selecting Get help → View
documentation in the Access IBM menu. Adaptec SCSI documentation
is also on the Software Selections CD that comes with your computer.
The diskette drive, hard disk drive, and CD-ROM drive that are
preinstalled in your computer come with power and signal cables
attached. If you replace any drives, it is important to remember which
cable is attached to which drive.
When you install a drive, ensure that the drive connector at the end of
the signal cable is always connected to a drive; also, ensure that the
drive connector at the other end is connected to the system board. This
reduces electronic noise from the computer.
If two IDE devices are used on a single cable, one must be designated
as the primary or master device and the other a secondary or
subordinate device; otherwise, some of the IDE devices might not be
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IntelliStation User Guide