Dell Precision 610 - Manual (Page 52)

Using the Integrated SCSI Controllers: Dell™ Precision™
WorkStation 610 Mini Tower Systems
Overview SCSI Device Considerations Installing SCSI Drivers
Overview
This chapter provides instructions for installing drivers for the following SCSI controllers:
Integrated Adaptec 7890 Ultra2/Wide low voltage differential (LVD) small computer system interface (SCSI) controller. This
primary controller provides transfer rates of up to 80 megabytes per second (MB/sec) with LVD hard-disk drives and up to
40 MB/sec with non-LVD hard-disk drives. The chassis supports up to four hard-disk drives of either type or a mix of both
types.
Adaptec 7880 Ultra/Wide external and narrow internal SCSI controller. This secondary controller provides transfer rates of up
to 40 MB/sec and is used for removable media devices such as CD-ROM drives and tape drives. This controller also
supports up to 15 external SCSI devices through a 68-pin connector on the computer's back panel. The chassis supports up
to three SCSI removable-media devices.
NOTES: To achieve 80-MB/sec data transfer rates on the primary SCSI channel, you must use LVD hard-disk drives
and either an LVD terminator or a multimode terminator.
If you install a mix of LVD and non-LVD hard-disk drives, the system can only achieve 40-MB/sec data transfer rates for
all SCSI drives. In addition, the LVD drives in this mix must be capable of reverting to 40 MB/sec. In this configuration,
you can terminate the SCSI subsystem with either a single-ended or multimode terminator.
Dell ships multimode terminators only, regardless of system configuration.
The total length of the SCSI cable for the secondary SCSI channel is 2.5 meters (m) for four attached devices.
The total number of SCSI devices connected to the secondary 7880 controller, both internally and externally, cannot
exceed 15.
SCSI Device Considerations
The 5.25-inch externally accessible drive bays at the front of the computer are normally used for non-hard-disk drive devices such
as CD-ROM drives and/or tape drives. These can be enhanced integrated drive electronics (EIDE) or SCSI devices.
CAUTION: Your hard-disk drive subsystem must consist of either SCSI hard-disk drives or EIDE hard-disk drives.
Dell does not support a mix of both types of hard-disk drives.
The four internal drive bays (located in the drive cage beneath the externally accessible drive bays; see Figure 7-1) are used for
either SCSI hard-disk drives or EIDE hard-disk drives. Internal hard-disk drives are mounted vertically in a removable drive bracket
that can contain up to four 1-inch hard-disk drives or up to two 1-inch and two 1.6-inch hard-disk drives.
NOTE: Dell supports only the drives it furnishes.