WD Caviar SE hard drives utilize an 8 MB buffer -- four times the industry norm -- to increase performance levels higher than any other IDE hard drive.

General
Rotational Speed 7,200 RPM (nominal)
Buffer Size 8 MB
Average Latency 4.20 ms (nominal)
Contact Start/Stop Cycles 50,000 minimum

Seek Times (Average)
Read Seek Time (Average) 8.9 ms
Write Seek Time (Average) 10.9 ms (average)
Track-To-Track Seek Time 2.0 ms (average)
Full Stroke Seek 21.0 ms (average)

Transfer Rates
Buffer To Disk 591 Mbits/s (Max)
Buffer to Host (EIDE)
Mode 5 Ultra ATA 100.0 MB/s
Mode 4 Ultra ATA 66.6 MB/s
Mode 2 Ultra ATA 33.3 MB/s
Mode 4 PIO 16.6 MB/s
Mode 2 multi-word DMA 16.6 MB/s

Cylinders 16,383
Number of Heads (Logical) 16
Number of Heads (Physical) 2
Sectors Per Track 63

Formatted Capacity 40,020 MB
Capacity 40 GB
Interface EIDE
Actuator Type Rotary Voice Coil
Number of Platters 1
Bytes Per Sector 512
User Sectors Per Drive 78,165,360
Servo Type Embedded

Height (English) 1.028 Inches (Max)
Length (English) 5.787 Inches (Max)
Width (English) 4.00 Inches (+/.......

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