HARD DISK 320GB SATA WD

Performance Specifications
	Rotational Speed	7,200 RPM (nominal)
	Buffer Size	16 MB
	Average Latency	4.20 ms (nominal)
	Load/unload Cycles	50,000 minimum

Seek Times
	Read Seek Time	8.9 ms
	Write Seek Time	8.9 ms (average)
	Track-To-Track Seek Time	0.6 ms (average)
	Full Stroke Seek	21.0 ms (average)

Transfer Rates
	Buffer To Host (Serial ATA)	3 Gb/s (Max)

Physical Specifications
	Formatted Capacity	320,072 MB
	Capacity	320 GB
	Interface	SATA 3 Gb/s
	User Sectors Per Drive	625,142,448

Physical Dimensions
English
	Height	1.028 Inches
	Length	5.787 Inches
	Width	4.00 Inches
	Weight	1.61 Pounds

Metric
	Height	25.4 mm
	Length	147 mm
	Width	101.6 mm
	Weight	0.73 kg

Environmental Specifications
Shock
	Operating Shock (Read)	65G, 2 ms
	Non-operating Shock	250G, 2 ms

Acoustics
	Idle Mode	28 dBA (average)
	Seek Mode 0	33 dBA (average)
	Seek Mode 3	29 dBA (average)

Temperature (English)
	Operating	41° F to 131° F
	Non-operating	-40° F to 149° F

Temperature (Metric)
	Operating	5° C to 55° C
	Non-operating	-40° C to 65° C

Humidity
	Operating	5-95% RH non-condensing
	Non-operating	5-95% RH non-condensing

Altitude (English)
	Operating	-1,000 feet to 10,000 feet
	Non-operating	-1,000 feet to 40,000 feet

Altitude (Metric)
	Operating	-305M to 3,050M
	Non-operating	-305M to 12,200M

Vibration
	Operating
	Linear	20-300 Hz, .75G (0 to peak)
	Random	10-300 Hz, 0.004 g² / Hz

	Non-operating
	Low Frequency	5-20 Hz, 0.195 inches (double amplitude)
	High Frequency	20-500 Hz, 4.0G (0 to peak)

Electrical Specifications
Current Requirements
	12 VDC
	Read/Write	450 mA
	Idle	430 mA
	Standby	20 mA
	Sleep	20 mA

	5 VDC
	Read/Write	800 mA
	Idle	730 mA
	Standby	270 mA
	Sleep	250 mA

	Power Dissipation
	Read/Write	9.50 Watts
	Idle	8.75 Watts
	Standby	1.60 Watts
	Sleep	1.50 Watts

As used for storage capacity, one megabyte (MB) = one million bytes, one gigabyte (GB) = one billion bytes, and one terabyte (TB) = one trillion bytes. Total accessible capacity varies depending on operating environment. As used for buffer or cache, one megabyte (MB) = 1,048,576 bytes. As used for transfer rate or interface, megabyte per second (MB/s) = one million bytes per second, megabit per second (Mb/s) = one million bits per second, and gigabit per second (Gb/s) = one billion bits per second.