Sas Drive Specifications; Conclusion - HP 418371-B21 - Dual Port 72 GB Hard Drive Technology Brief

SAS drive specifications

Table 3 compares the seek time and power consumption of SFF (2.5-inch) SAS drives available from
HP at time of publication.
NOTE:
Drive types and specifications are subject to change without notice.
Refer to the following site for a listing and specifications of
currently available SAS drives:
http://h18004.www1.hp.com/products/servers/proliantstorage/
serial/sas/index.html
Table 3. Comparison of seek time and power consumption of HP SFF SAS drives
Capacity/RPM
Seek time:
Single track
Average
Full stroke
Power consumption:
Idle
Maximum
NOTE: All drives listed In Table 3 have a cache/buffer size of 16 MB and a transfer time of 3 Gb/s.

Conclusion

A variety of hard drive types are used in today's server industry. The right HDD type is the one that
provides the best return on investment (ROI) for a particular server application. Small-to-medium
businesses (SMBs) or environments with less-than-demanding applications can be well served with
SCSI or SATA drives that offer economical service and good dollar-per-gigabyte value.
In the mission-critical, performance-oriented, enterprise server environment where hard drive duty
cycle is 100 percent, SFF SAS drives excel in performance and reliability. Since SFF drives require
only 70 percent of the space and half the power of 3.5-inch drives, higher drive densities per U
space can be achieved without a significant increase in power consumption. Higher drive densities
provide better overall performance, reliability, and lower operating costs.
36 GB/15K 72 GB/10K
0.20 ms 0.20 ms
3.0 ms 4.0 ms
7.0 ms 8.1 ms
5.74 watts 5.96 watts
7.25 watts 8.42 watts
72 GB/15K 146 GB/10K
0.20 ms 0.60 ms
3.0 ms 4.1 ms
7.0 ms 8.0 ms
6.11 watts 6.31 watts
8.29 watts 8.73 watts
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