Seagate ST3146954FC Performance, Reliability, Formatted capacities, Programmable drive capacity

3.3Performance

•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

3.4Reliability

•1,400,000 hour MTBF

•Increased LSI circuitry integration

•Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)

•Dithering

3.5Formatted 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:

	ST336854FC		ST373554FC		ST3146954FC
Sector Size	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

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.

3.5.1Programmable 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

Cheetah 15K.4 FC Product Manual, Rev. B 9