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Cable Suggestions

System throughput problems can occur if SCSI cable use is not maximized. You should:

Use cables up to 12 meters for LVD devices.

For single ended SCSI devices, use the shortest SCSI cables (no more than 3 meters for Fast SCSI, no more than 1.5 meters for an 8-drive Ultra2 SCSI system and no more than 3 meters for a 6-drive Ultra2 SCSI system.)

Use active termination.

Use only Dell-approved cables.

Step 7—Set Target IDs

Set target identifiers (TIDs) on the SCSI devices. Each device in a specific SCSI channel must have a unique TID in that channel. See the documentation for each SCSI device to set the TIDs. The PERC 3/QC controller automatically occupies TID 7 in the SCSI channel. Eight-bit SCSI devices can only use the TIDs from 0 to 6. 16-bit devices can use the TIDs from 0 to 15. The arbitration priority for a SCSI device depends on its TID.

Ta b l e

1 0 - 8 . Ta r g e t I D s

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Priority

Highest

 

 

 

 

Lowest

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TID

 

7

6

5

...

2

1

0

15 14 ...

9

8

 

 

 

 

 

 

 

 

 

 

 

 

Step 8—Power on Host System

Replace the computer cover and reconnect the AC power cords. Turn power on to the host computer. Set up the power supplies so that the SCSI devices are powered up at the same time as or before the host computer. If the computer is powered up before a SCSI device, the device might not be recognized.

During boot, the PERC 3/QC BIOS message appears:

PowerEdge Expandable RAID Controller BIOS Version x.xx date

Copyright (c) Dell Computer Corporation

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PERC 3/QC Hardware Installation

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