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Integration Guide for New Dual-Core Intel

Xeon

Processor-Based Servers (or Workstations) Rev 1.0

Figure 3.6.2 Bandwidths of seven generations of SCSI

SCSI hard drives provide some benefits:

¾ Fast data transfer (up to 320 MB/s transfer rate per channel)

¾ High MTBF (Mean Time between Failures)

¾ Support multiple HDD on one channel, such as a single channel of Ultra 320 can support 15 hard

drivers, two channels can support up to 30 hard drivers, and all of hard drivers in the same

channel use only one IRG

¾ SCSI controller can offload some CPU tasks which used to handling the storage commands; CPU

utilization rate for SCSI HDD processing is low. This is good for multiple task system.

2) SATA HDD

Serial ATA 1.0 (SATA)

SATA 1.0 specification was developed in 2001, SATA is the first generation of the new disk interface

technology replacing Parallel ATA. In desktops, SATA is expected to replace Parallel ATA as the

primary internal storage for PCs. SATA1.0 delivers a maximum data transfer rate of 1.5 Gb/sec (150

MB/sec) per port and its future roadmap shows growth to 6.0 Gb/sec (600 MB/sec). Advantages of

SATA include a point-to-point interconnect that enables full bandwidth available to each device,

lower pin-count, lower voltage, hot-plug capability, thin cabling, longer cable length and

NAS and some Storage Area Network (SAN) systems where Parallel ATA may not have been

considered.

Serial ATA II (SATA II)

SATA II is the second-generation SATA disk interface technology currently under development by

the SATA working group. The SATA II specification picks up where SATA 1.0 left off, and will be

deployed in 2 phases. The first phase, called “Extensions to Serial ATA 1.0”, focuses primarily on

addressing the needs of servers and networked storage. These include queuing, enclosure services,

hot plug, cold presence detect, cabling and backplane improvements. The second phase is

anticipated to scale performance to 3.0 Gb/sec (300 MB/sec) per port. These combined

enhancements will make SATA II a good option for DAS, NAS and SAN storage systems where

price/performance and cost are key factors.