Momentus XT Product Manual, Rev. A 3
2.0 Drive specifications
Unless otherwise noted, all specifications are measured under ambient conditions, at 25°C, and nominal
power.
2.1 Specification summary table
The specifications listed in this table are for quick reference. For details on specification measurement or defi-
nition, see the appropriate section of this manual.
Table 1: Drive specifications
Drive specification ST95005620AS ST93205620AS ST92505610AS
Formatted GB (512 bytes/sector)* 500 320 250
Guaranteed sectors 976,773,168 625,142,448 488,397,168
Bytes per sector 512
Physical read/write heads 4 3 2
Discs 2 1
Cache (MB) 32
Recording density in BPI (bits/in max) 1,490k
Track density TPI (tracks/in max) 265k
Areal density (Gb/in
2
max) 394
Spindle speed (RPM) 7200
Average latency (ms) 4.17
Internal transfer rate (Gb/s max) 1.23
I/O data transfer rate (Gb/s max) 3.0
ATA data-transfer modes supported SATA 1.0, Serial ATA Revision 2.6
PIO modes 0–4
Multiword DMA modes 0–2
Ultra DMA modes 0–6
Height (max) 9.5 +/- 0.2 mm (0.370 +/- .008 in)
Width (max) 69.85 +/- 0.25 mm (2.750 +/- 0.010 in)
Length (max) 100.35 +0.20 / -0.25 mm (3.951 +0 .008 / -0.010 in)
Weight (max) 110 g (0.238 lb) 105 g (0.227 lb)
Power-on to ready (sec typical) 4.5
Standby to ready (sec typical) 3.0
Track-to-track seek time, read (msec typical) 1.5
Average seek, read (ms typical) 11.0
Average seek, write (ms typical) 13.0
Startup current, +5V amps (max) 1.0
Seek power (watts typical) 2.2