Seagate Cheetah 15K.4 SAS, Product Manual

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Cheetah 15K.4 SAS Product Manual, Rev. B 9
3.4 Reliability
• Annualized Failure Rate (AFR) of 0.62%
• LSI circuitry
• Balanced low mass rotary voice coil actuator
• 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.4 SAS Installation Guide (part number 100350602).
Capacity (Blocks)
Sector Size
ST3146854SS ST373454SS ST336754SS
Decimal Hex Decimal Hex Decimal Hex
512 286,749,488 11177330 143,374,744 88BB998 71,687,372 445DCCC
514 282,050,768 10CFC0D0 141,025,384 867E068 70,512,692 433F034
520 280,790,184 10BC84A8 140,395,092 85E4254 70,197,546 42F212A
522 279,041,740 10A1D6CC 139,463,602 8500BB2 68,914,176 41B8C00
524 275,154,368 106685C0 137,577,184 83342E0 68,766,592 4194B80