Dell Perc 5i
The Dell Perc 5i is a PCIe x8 SAS/SATA RAID card fitted to many Dell PowerEdge servers such as the PE1950 and PE2950. The card supports RAID 0, 1, 10, 5 and 50 and is reasonably priced on eBay considering the performance of the card.
The card is also available with external connectors (the Perc 5/E) and a cut-down version (the Perc 5/iR) which does not support write caching.
- Device Type: Serial Attached SCSI Raid Controller Card
- Interface Type: x8 PCI Express
- Processor: Intel® IOP333
- Cache Size: 256MB (512MB upgradable)
- Channel Qty: 8
- Port and Connector Type: 2x SFF-8484 Connectors
- RAID Levels: RAID 0, RAID 1, RAID 5, RAID 10, RAID 50
The card has two SFF-8484 connectors providing direct connection for 8 SAS or SATA drives, with appropriate cables, or connection to a hot-plug backplane.
The card can get close to 300MB/s sustained write in RAID-5 and 400MB/s+ otherwise (with enough drives). SATA NCQ is not supported which makes the controller unsuited to SSDs although they will usually work.
The latest Dell firmware is available from dell.com. Some users prefer to use LSI firmware.
Fittment to Unsupported Machines
The card can be fitted to most systsms, but some Intel based chipsets require a 'pin mod' (where pins 5 and 6 on the PCIe connector are covered, for example using insulation tape or nail varnish).
When used in a machine other than an officially supported PowerEdge server, additional cooling must be provided as the heatsink fitted to the IOP333 (which has a TDP of about 11W) is dependent on forced airflow. A large northbrige heatsink is usually sufficient, especially if in the flow path of a case fan.
An extensive thread on the Perc 5i can be found on Overclockers.
Cache and Battery Backup
An optional 7w LiIon battery (available as service kit XJ547) provides up to 72 hours of backup to the cache in the event of power failure. If power is restored within this time, uncommitted writes are flushed in the controllers BIOS phase. The battery and cable are interchangable with that available for the Perc 6i controller.
The card is only available from Dell with 256MB cache but can be upgraded to 512MB by replacing the DIMM (and according to the chipset specs, possibly 1GB), but the correct RAM type must be used:
- PC2-3200 333MHz 240-pin ECC Registered DIMM
- 64x8 organisation
- Single sided, single rank
A suitable 512MB module is the Samsung M393T6553BG0-CCC.