IBM IntelliStation 6836, Hardware Maintenance Manual

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For normal operations of the system, a jumper is installed on pins 2 and 3 of the
boot block jumper. See “Recovering BIOS” on page 17 for information about the
boot block jumper.
CMOS jumper
For normal operation of the system, a jumper is installed on pins 1 and 2 of the
CMOS jumper. See “Clearing CMOS” on page 21 for information about the CMOS
jumper.
Power and signal cables for internal drives
Your computer uses cables to connect IDE and SCSI drives to the power supply
and to the system board. The following cables are provided:
v
Four-wire power cables connect the 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.
v
Flat signal cables, also called ribbon cables, connect IDE, SCSI, and diskette
drives to the system board. There are two sizes of ribbon signal cables that come
with your computer.
– The wider IDE signal cable has two or three connectors.
- If the cable has three connectors, one of these connectors is attached to the
drive, one is a spare, and the third attaches to the primary or secondary
IDE connector on the system board.
- If the cable has two connectors, one of these connectors is attached to the
hard disk drive, and the other attaches to the primary or secondary IDE
connector on the system board.
Notes:
1. If you want to add another device, and your computer does not come
with a CD-ROM drive preinstalled, you will need a second signal cable
with three connectors. You will need an 80-conductor ATA 66 signal
cable if you are replacing the existing signal cable or adding a second
hard disk drive. ATA 66 signal cables are color-coded. The blue
connector attaches to the system board; the black connector attaches to
the master device, and the gray middle connector attaches to the slave
device.
If your computer comes with a CD-ROM drive, it will have an ATA 66
signal cable. However, if you are installing a hard disk drive, you must
change the switch setting on the CD-ROM drive to secondary and
change the connector used for the CD-ROM drive to the gray middle
connector.
2. If you are installing a slimline CD-ROM drive in the small form factor
desktop model, the IDE cable requires a special connector to attach to
the slimline CD-ROM drive. This connector can be attached only to an
optional slimline CD-ROM drive.
– The narrower signal cable has two connectors, one to attach to the diskette
drive and the other to attach to the connector (FDD1) on the system board.
Note: To locate connectors on the system board, see “System board internal cable
connectors” on page 32.
The following are some important points to remember when connecting power and
signal cables to internal drives:
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Hardware Maintenance Manual: IBM IntelliStation Type 6836, 6846