|
Using the Integrated SCSI Controllers: Dell Precision WorkStation 420 Systems
User's Guide
Back to Contents Page
Using the Integrated SCSI Controllers: Dell Precision™
WorkStation 420 Systems User's Guide
This section provides instructions for installing drivers for the
integrated dual-channel Adaptec 7899 Ultra160/m low-voltage differential (LVD) small
computer system interface (SCSI) controller. This controller provides transfer rates of up
to 160 megabytes per second (MB/sec) with LVD hard-disk drives on the primary channel, and
up to 40 MB/sec with non-LVD hard-disk drives on the secondary channel. The primary
channel also supports Ultra2 and Ultra SCSI. The desktop chassis supports up to two
hard-disk drives, and the mini tower chassis supports up to four hard-disk drives.
 |
NOTES: To achieve 160-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 maximum total length of the SCSI cable for the primary SCSI
channel is 12 meters (m). The maximum total length of the SCSI cable for the
secondary SCSI channel is 0.5 m with eight devices or 1 m with four devices.
The total number of SCSI devices connected to the secondary 7899
controller, both internally and externally, cannot exceed 15. |
The 5.25-inch externally accessible drive bays at the front of the
computer are 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.
NOTICE: 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 desktop chassis has two internal drive bays (located in the
drive cage next to the externally accessible drive bays; see Figure 1) that can
accommodate either two SCSI hard-disk drives or two EIDE hard-disk drives. Internal
hard-disk drives are mounted vertically in a removable drive bracket that can contain two
1.6-inch hard-disk drives.
|
NOTE: Dell supports only the drives it
furnishes. |
Figure
1. Internal Drive Bays (Desktop Chassis)
|
| 1 |
Two-bay hard-disk drive cage (internal) |
|
The mini tower chassis has four internal drive bays (located in the
drive cage beneath the externally accessible drive bays; see Figure 2) that can
accommodate either two EIDE hard-disk drives or four SCSI hard-disk drives. Internal
hard-disk drives are mounted vertically in a removable drive bracket that can contain four
1-inch hard-disk drives, two 1-inch and two 1.6-inch hard-disk drives, or three 1.6-inch
hard-disk drives.
Figure
2. Internal Drive Bays (Mini Tower Chassis)
|
| 1 |
Four-bay hard-disk drive cage (internal) |
|
See "Installing SCSI Devices" for detailed
information about installing drives in the externally accessible or internally accessible
drive bays.
Dell installed the SCSI drivers for your system on your system's
hard-disk drive. Backup copies of these drivers are provided on the Dell Precision
ResourceCD. If your system's SCSI drivers are ever inadvertently erased or corrupted,
you must reinstall them. For instructions on reinstalling these drivers, refer to the
documentation that came with your Dell Precision Resource CD.
|
NOTE: SCSI Drivers for the Linux operating system
are included with the Linux operating system and distribution media. They are not provided
on the Dell Precision ResourceCD. |
Back to Contents Page
| 
