HP DC5850 - Manual (Page 52)

5-2 www.hp.com Technical Reference Guide
Input/Output Interfaces
5.2 SATA Interfaces
These systems provide four serial ATA (SATA) interfaces that support tranfer rates up to 3.0
Gb/s and offer RAID data protection functionality. The SATA interface duplicates most of the
functionality of the EIDE interface through a register interface that is equivalent to that of the
legacy IDE host adapter.
5.2.1 SATA Connector
The standard 7-pin SATA connector is shown in the figure below.
Figure 5-1. 7-Pin SATA Connector (P60-P63 on system board).
5.2.2 AHCI/RAID Support
The SATA controller of the SB700 South Bridge can be set operate in either an IDE or AHCI
RAID configuration. The AHCI RAID configuration supports RAID 0 and RAID 1 for
improving performance and/or reliability. Applied to systems with only one hard drive, AHCI
RAID can improve system performance somewhat through use of native command queuing
(NCQ). True fault tolerance requires the use of two or more hard drives to allow mirroring,
parity, and/or striping.
CAUTION: Changing the storage mode should always be preceded by backing up all hard
rive data onto secondary media.
RAID 0—Striping with Two Hard Drives
RAID 0 uses striping to improve performance but does not provide any fault tolerance. The lack
of redundancy (a failed drive ruins the whole array) results in less than half the reliability of a
single hard drive. Although these systems support RAID 0, it is not the recommended
configuration.
Table 5-1.
7-Pin SATA Connector Pinout
Pin Description Pin Description
1 Ground 6 RX positive
2 TX positive 7 Ground
3 TX negative A Holding clip
4 Ground B Holding clip
5 RX negative -- --
Pin 1 Pin 7
A B