Seagate Cheetah 15K.5 SAS ST373455SS - Manual (Page 17)

Cheetah 15K.5 SAS Product Manual, Rev. E 11
4.0 Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of
Cheetah drives.
4.1 Internal drive characteristics
ST3300655SS ST3146855SS ST373455SS
Drive capacity 300.0 146.8 73.4 Gbytes (formatted, rounded off value)
*,**
Read/write data heads 8 4 2
Tracks per surface (total) 74,340 74,340 74,340 Tracks (user accessible)
Tracks per inch 125,000 125,000 125,000 TPI
Peak bits per inch 890 890 890 KBPI
Areal Density 110 110 110 Gbits/inch 2
Internal data rate 960 to 1607 960 to 1607 960 to 1607 Mbits/sec (variable with zone)
Disc rotation speed 15k 15k 15k RPM
Avg rotational latency 2.0 2.0 2.0 msec
*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment
and formatting.
**Rounded off value.
4.2 Seek time
See Section 9.4.1, "SAS physical interface" on page 57 and the SAS Interface Manual (part number
100293071) for additional timing details.
4.2.1 Access time
Not Including controller overhead
1 , 2
(msec)
1. Typical access times are measured under nominal conditions of temperature, voltage, and
horizontal orientation as measured on a representative sample of drives.
2. Access to data = access time + latency time.
Read Write
Average Typical 3.5 4.0
Single track Typical 0.2 0.4
Full stroke Typical 6.8 7.5