Dell 3 - Manual (Page 27)

Overview 25
• Two internal and four external connectors for the PERC 3/QC, two
internal and two external connectors for the PERC 3/DC and PERC
3/DCL, and one internal and one external connector for the PERC
3/SC
• RAID levels 0 (striping), 1 (mirroring), 5 (distributed parity), 10
(combination of striping and mirroring), and 50 (combination of
striping and distributed parity)
• Advanced array configuration and management utilities
• Battery backup for up to 72 hours for the PERC 3/QC and PERC
3/DC
NOTE: Clustering is not
supported by PERC 3/QC
or PERC 3/DCL.
• Up to 12 SCSI drives per channel using the Dell PowerVault 21xS
storage system or 14 SCSI drives using the Dell PowerVault 22xS
SCSI Channels
The PERC 3/QC controller card includes four SCSI channels. There are two
QLogic
®
12160 chips; each chip controls two SCSI channels.
The PERC 3/DC and PERC 3/DCL controller cards include two SCSI
channels. There is one QLogic 12160 chip, which controls two SCSI
channels.
The PERC 3/SC controller card has one SCSI channel. There is one QLogic
10160 chip.
Non-volatile Random Access Memory (NVRAM) and Flash Read-
only Memory (ROM)
A 32 KB x 8 NVRAM stores RAID system configuration information. The
PERC 3 firmware is stored in flash ROM for easy upgrade.
SCSI Connectors
PERC 3/QC has four ultra-high-density 68-pin external connectors for the
external storage subsystem and two high-density 68-pin internal connectors.
PERC 3/DC and PERC 3/DCL have two ultra-high-density 68-pin external
connectors for the external storage subsystem and two high-density 68-pin
internal connectors.