Technologies in HP ProLiant G6 c-Class server blades with AMD Opteron™ processors

Figure 6. PCI Express bandwidth

Link

size

Max. bandwidth

(Send or receive)

Total

Bandwidth

(Send and

receive)

x1 250 MB/s 500 MB/s

x4 1 GB/s 2 GB/s

x8 2 GB/s 4 GB/s

A PCIe 2.0 device can be used in a PCIe 1.0 slot. For

best performance, however, each card should

be used in a slot that supports its logical link size.

HP Smart Array controllers

ProLiant c-Class server blades with AMD processors support SAS and SATA SFF drives through

integrated or optional HP Smart Array controllers. The ProLiant BL465c G6 server blade uses the

Smart Array E200i controller. The BL685c G6 server blade uses the Smart Array P400i controller or

the embedded SATA controller. The BL495c G6 has an embedded SATA controller, and an optional

Smart Array P700m controller is available to connect drives externally.

A battery-backed write cache (BBWC) is available as an option for the Smart Array controllers. The

battery prevents information in the buffer from being lost in case of an unexpected system shutdown.

In the case of a complete system failure, IT administrators can move the controller and disks to a

different server, where the controller will flush out the cache to the disks after power is restored. In the

case of a controller failure, administrators can move the cache module and disks to a working

controller, where the cache will be flushed out to the disks. The battery will last up to two days without

receiving any power from the server.

Serial Attached SCSI technology

SAS is a serial communication protocol for direct-attached storage devices such as SAS and SATA

Small Form Factor (SFF) disk drives. It is a point-to-point architecture in which each device connects

directly to a SAS port rather than sharing a common bus, as parallel SCSI devices do. Point-to-point

links increase data throughput and improve the ability to locate and fix disk failures. More

importantly, SAS architecture solves the parallel SCSI problems of clock skew and signal degradation

at high signaling rates.

For more information about SAS technology, refer to the HP technology brief titled “Serial Attached SCSI

storage technology”:

http://h20000.www2.hp.com/bc/docs

/support/SupportManual/c01613420/c01613420.pdf.