Seagate cheetah st373554fc Manual Do Utilizador

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Cheetah 15K.4 FC Product Manual, Rev. B
9
3.3
Performance
• Programmable multi-segmentable cache buffer 
• 200 Mbytes/sec maximum instantaneous data transfers per port
• 15k RPM spindle; average latency = 2.0 msec
• Command queuing of up to
 
128 commands
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
• Adaptive seek velocity; improved seek performance
3.4
Reliability
• 1,400,000 hour MTBF
• Increased LSI circuitry integration
• Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)
• Dithering
3.5
Formatted capacities
Standard OEM models are formatted to 512 bytes per block. The sector size is selectable at format time. 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 sector 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 sector size, but the excess 
capacity above the guaranteed level will vary between 10K and 15K families and from generation to gener-
ation, depending on how each sector 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.
3.5.1
Programmable drive capacity
Using the Mode Select command, the drive can change its capacity to something less than maximum. See the 
Mode Select Parameter List table in the SCSI Interface Product Manual. Refer to the Parameter list block 
descriptor number of blocks field. A value of zero in the number of blocks field indicates that the drive shall not 
Sector Size
ST336854FC
ST373554FC
ST3146954FC
Decimal
Hex
Decimal
Hex
Decimal
Hex
512
71,687,372
445DCCC
143,374,744
88BB998
286,749,488
11177330
514
70,512,692
433F034
141,025,384
867E068
282,050,768
10CFC0D0
520
70,197,546
42F212A
140,395,092
85E4254
280,790,184
10BC84A8
522
68,914,176
41B8C00
139,463,602
8500BB2
279,041,740
10A1D6CC
524
68,766,592
4194B80
137,577,184
83342E0
275,154,368
106685C0