Hitachi IC25N010ATCS04, Specifications

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4.4 Performance characteristics
Drive performance is characterized by the following parameters:
!
Command Overhead
!
Mechanical Positioning
#
Seek Time
#
Latency
!
Data Transfer Speed
!
Buffering Operation (Look ahead/Write Cache)
Note: All the above parameters contribute to drive performance. There are other parameters which contri-
bute to the performance of the actual system. This specification defines the essential characteristics of the
drive. This specification does not include the system throughput as this is dependent upon the system and
the application.
The following table gives a typical value for each parameter. The detailed descriptions are found in
section 5.0.
100 100 Buffer-host data transfer (MB/s)
130-245
125-241
146-261 Disk-buffer data transfer (Mb/s)
1.0 1.0 Command overhead (ms)
3.0 5.0 Power-on-to-ready (sec)
4200 5400 Rotational Speed (RPM)
14 14 Average Random Seek Time - Write (ms)
12 12 Average Random Seek Time - Read (ms)
All other models 60-GB Function
Figure 8. Performance characteristics
4.4.1 Command overhead
Command overhead time is defined as the interval from the time that a drive receives a command to the
time that the actuator starts its motion.
Hitachi Travelstar 60GH & 40GN hard disk drive specifications
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