Removal and Replacement Procedures
3-19
Compaq Confidential – Need to Know Required
Writer: Bruce Sullivan Project: Compaq Deskpro Workstation AP250 Maintenance and Service Guide Comments:
Part Number: 118133-001 File Name: d-ch3 Removal and Replacement Procedures.doc Last Saved On: 10/26/99 3:02 PM
Installing Optional SCSI Devices
Select models of the Compaq Deskpro Workstation AP250 have a preinstalled
internal SCSI hard drive. You can install additional SCSI devices using the
external SCSI connector located on the rear panel of the workstation.
Important Guidelines for Installing Optional SCSI
Devices
If you are installing additional SCSI devices, you MUST adhere to the
following guidelines:
■
To preserve data integrity, do not install more than seven SCSI devices
per SCSI controller.
■
The Wide-Ultra2 SCSI controller requires that a unique SCSI ID (0-7)
be set for each SCSI device installed. The controller identifies a SCSI
device by its SCSI ID number rather than its location. Moving a SCSI
device from one position to another on the SCSI chain does not affect
communication between the controller and the SCSI device. The
reserved and available SCSI ID numbers for SCSI devices are as
follows:
Y
SCSI ID 0 is reserved for the primary hard drive.
Y
SCSI ID 7 is reserved for the controller.
Y
SCSI IDs 1 through 6 are available.
■
Every SCSI chain or circuit must be terminated (closed) at both ends. If
using a terminated cable, disable the termination for all devices. If using
a non-terminated cable, only disable the termination for the last device
on the chain.
■
Turn on an external SCSI device before turning on power to the
workstation. This enables the system board controller to recognize the
external SCSI device. When external SCSI devices are connected to the
external SCSI connector on the rear panel of the workstation, that device
becomes the end of the SCSI chain and must be terminated.
CAUTION:
Do not route cables near the intake to the power supply. Cables
routed in this manner may block airflow to the power supply, causing it to
overheat.