Seagate Momentus ST9250827AS 2.5″ SATA 250GB 5.4K Hard Drive

Capacity: 250GB
Spindle Speed: 5,400RPM
Interface Type: SATA
Disk Size: 2.5″x9mm (Fits in ALL laptops)
Sustained Throughput (MBps): 58
Average Seek Time (read/write ms): 12 / 14
Electrical Interface Speed: SATA 300 – 3.0Gbps
On-Board Cache: 8MB

These drives provide the following key features:
• 5,400-RPM spindle speed.
• 8-Mbyte buffer.
• Quiet operation. Fluid Dynamic Bearing (FDB) motor.
• High instantaneous (burst) data-transfer rates (up to 150 Mbytes per second).
• Perpendicular recording TECHNOLOGY provides the drives with increased areal density.
• State-of-the-art cache and on-the-fly error-correction algorithms.
• Full-track multiple-SECTOR transfer capability without local processor intervention.
• 900 Gs nonoperating shock and 325 Gs of operating shock.
• SeaTools diagnostic software performs a drive self-test that eliminates unnecessary drive returns.
• The 3D Defense System™, which includes Drive Defense, Data Defense and Diagnostic Defense, offers the industry’s most comprehensive protection for disc drives.
• Support for S.M.A.R.T. drive monitoring and reporting.
• Support for Read Multiple and Write Multiple commands.
• Worldwide Name (WWN) capability uniquely identifies the drive

Dell Part Numbers: KW721 0KW721

Drive specification	ST9250827AS	ST9200827AS	ST9160827AS	ST9120817AS
Formatted Gbytes (512 bytes/SECTOR)*	250	200	160	120
Guaranteed SECTORS	488,397,168	390,721,968	312,581,808	234,441,648
Bytes per sector	512
Physical read/write heads	4		3	2
Discs	2
Cache (Mbytes)	8
Recording density in BPI (bits/inch max)	1,180k
Track density TPI (tracks/inch max)	173
Areal density (Gbits/inch max)	204
Spindle speed (RPM)	5,400
Internal transfer rate (Gbits/sec max)	778
Sustained transfer rate (Mbytes/sec max)	58
I/O data transfer rate (Mbytes/sec max)	300
ATA data-transfer modes supported	SATA 1.0, Serial ATA Revision 2.5 PIO modes 0–4 Multiword DMA modes 0–2 Ultra DMA modes 0–6
Height (max)	9.5 +/- 0.2 mm (0.374 +/- .0078 inches)
idth (max) 69.85 +/- .25 mm (2.750 +/- .010 inches)	69.85 +/- 0.25 mm (2.75 +/- 0.0098 inches)
Length (max)	100.20 +/- 0.25 mm (3.945 +/- 0.010 inches)
Weight (typical)	</=102 grams (0.23 lb)			97 grams (0.21 lb)
Average latency (msec)	5.6
Power-on to ready (sec typical)	<3.0
Standby to ready (sec typical)	<2.0
Track-to-track seek time, read (msec typical)	<2.0 (read), <2.5 (write)
Average seek, read (msec typical)	<12.0
Average seek, write (msec typical)	14.0
Startup current, +5V (max)	1.0 amps