Dell PERC 4/SI - Manual (Page 27)

The firmware automatically detects and rebuilds failed drives. This can be done transparently with hot spares.
RAID Controller Specifications
Table 3 -5 lists the RAID controller specifications.
Table 3-5. RAID Controller Specifications
SCSI Bus
The RAID adapter controls hard drives using Ultra320 SCSI buses (channels) over which the system transfers data in Ultra320 SCSI mode. The PERC 4/Si and
4e/Si controllers control one SCSI channel, while the PERC 4/Di and 4e/Di controls two. The SCSI channel supports up to 15 wide or seven non-wide SCSI
devices at speeds up to 320 MB/sec.
SCSI Termination
The RAID controller uses active termination on the SCSI bus conforming to SCSI-3 and SCSI SPI-4 specifications. Termination enable/disable is automatic
through cable detection.
SCSI Firmware
The RAID controller firmware handles all RAID and SCSI command processing and supports the features described in Table 3 -6 .
Parameter PERC 4/Di/Si PERC 4e/Di/Si
Processor Intel ® i303 64-bit RISC processor @ 100 MHz Intel ® IOP332 I/O processor with Intel XScale
Technology
Bus type PCI Rev. 2.2 PCI Express Rev. 1.0a
PCI Express controller Intel i303 Intel i303
Bus data transfer rate Up to 532 MB/sec at 64/66 MHz Up to 4 GB/sec
Cache memory size 128 MB 256 MB (DDR2)
Cache function Write-back, Write-through, Adaptive read-
ahead, Non read-ahead, Read-ahead
Write-back, Write-through, Adaptive read-
ahead, Non read-ahead, Read-ahead
Flashable firmware 1 MB x 8 flash ROM 4 MB × 16 flash ROM
Nonvolatile random access memory (NVRAM) 32 KB × 8 for storing RAID configuration 32 KB × 8 for storing RAID configuration
SCSI data transfer rate Up to 320 MB/sec per channel Up to 320 MB/sec per channel
SCSI bus LVD or single-ended LVD
SCSI termination Active Active
Termination disable Automatic through cable and device detection Automatic through cable and device detection
Devices per SCSI channel Up to 15 wide or seven narrow SCSI devices Up to 15 wide or seven narrow SCSI devices
SCSI device types Synchronous or asynchronous Synchronous or asynchronous
RAID levels supported 0, 1, 5, 10, and 50 0, 1, 5, 10, and 50
Multiple logical drives/arrays per controller Up to 40 logical drives per controller Up to 40 logical drives per controller
Online capacity expansion Yes Yes
Dedicated and pool hot spare Yes Yes
Hot swap devices supported Yes Yes
Non-disk devices supported
NOTE: PERC 4/Di/Si and 4e/Di/Si do not support any
non- disk devices except backplanes.
Yes Yes
Mixed capacity hard drives Yes Yes