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Barracuda Serial ATA V Product Manual, Rev. B 7
2.4 Physical organization
2.5 Recording and interface technology
2.6 Physical characteristics
Drive model Read/write heads Number of discs
ST3120023AS 4 2
ST380023AS 3 2
ST360015AS 2 1
Interface Serial ATA (SATA)
Recording method 16/17 EPRML
Recording density BPI (bits/inch max) 542,000
Track density TPI (tracks/inch max) 78,000
Areal density (Mbits/inch
2
max) 42,200
Spindle speed (RPM) (± 0.2%) 7,200
Maximum Internal transfer rate (Mbits/sec) 570
Sustained transfer rate (Mbytes/sec) 27 to 44
I/O data-transfer rate (Mbytes/sec max) 16.6 (PIO mode 4)
100 (Ultra DMA mode 5)
150 (SATA 1.0)
Interleave 1:1
Cache buffer 8 Mbytes
Drive specification
Maximum height(mm)
(inches)
26.1
1.028
Maximum width(mm)
(inches)
101.85
4.01
Maximum length(mm)
(inches)
147.0
5.787
Typical weight(grams)
(pounds)
635
1.40