beautypg.com

4 reliability, 5 formatted capacities, 6 programmable drive capacity – Seagate Cheetah 15K.5 SAS ST373455SS User Manual

Page 15: 7 factory-installed accessories, Reliability, Formatted capacities, Programmable drive capacity, Factory-installed accessories

background image

Cheetah 15K.5 SAS Product Manual, Rev. E

9

3.4

Reliability

• 1,400,000 hour MTBF (Annualized Failure Rate (AFR) of 0.62%)
• Incorporates industry-standard Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)
• 5-year warranty

3.5

Formatted capacities

Standard OEM models are formatted to 512 bytes per block. The block size is selectable at format time and
must be a multiple of 4 bytes. Users having the necessary equipment may modify the data block size before
issuing a format command and obtain different formatted capacities than those listed.

To provide a stable target capacity environment and at the same time provide users with flexibility if they
choose, Seagate recommends product planning in one of two modes:

1.

Seagate designs specify capacity points at certain block sizes that Seagate guarantees current and future
products will meet. We recommend customers use this capacity in their project planning, as it ensures a
stable operating point with backward and forward compatibility from generation to generation. The current
guaranteed operating points for this product are:

2.

Seagate drives also may be used at the maximum available capacity at a given block size, but the excess
capacity above the guaranteed level will vary between other drive families and from generation to genera-
tion, depending on how each block size actually formats out for zone frequencies and splits over servo
bursts. This added capacity potential may range from 0.1 to 1.3 percent above the guaranteed capacities
listed above. Using the drives in this manner gives the absolute maximum capacity potential, but the user
must determine if the extra capacity potential is useful, or whether their assurance of backward and for-
ward compatibility takes precedence.

3.6

Programmable drive capacity

Using the Mode Select command, the drive can change its capacity to something less than maximum. See the
Mode Select (6) parameter list table in the SAS Interface Manual, part number 100293071. A value of zero in
the Number of Blocks field indicates that the drive will not change the capacity it is currently formatted to have.
A number other than zero and less than the maximum number of LBAs in the Number of Blocks field changes
the total drive capacity to the value in the Number of Blocks field. A value greater than the maximum number of
LBAs is rounded down to the maximum capacity.

3.7

Factory-installed accessories

OEM standard drives are shipped with the Cheetah 15K.5 SAS Installation Guide, part number 100384785,
and the Safety and Regulatory Agency Specifications, part number 75789512 (unless otherwise specified).

Capacity (Blocks)

Sector Size

ST3300655SS

ST3146855SS

ST373455SS

Decimal

Hex

Decimal

Hex

Decimal

Hex

512

585,937,500

22ECB25C

286,749,488

11177330

143,374,744

88BB998

520

573,653,847

22314357

280,790,184

10BC84A8

140,395,092

85E4254

524

566,007,800

21BC97F8

275,154,368

106685C0

137,577,184

83342E0

528

557,874,778

21407E5A

272,662,935

10408197

136,331,467

82040CB

This manual is related to the following products: