Gateway 40-GB 7200-RPM Hard Disk Drive - EWD400BB-22DEA0

Feature	Description
Manufacturer	Western Digital
Manufacturer model	WD400BB
Formatted capacity	40 020 MB
Interface	40-pin EIDE
Actuator type	Rotary Voice Coil
Number of Disks	1
Data Surfaces	2
Number of Heads	2
Bytes per sector	512
User sector per drive	78 165 360
Servo Type	Embedded
Recording Method EPR4	Rate 16/17 PRML
ECC	Reed Solomon
Head Park	Automatic
Average Seek (read)	8.9 ms average
Average Seek (write)	10.9 ms average
Track to Track Seek	2.0 ms average 5 ms maximum
Full Stroke Seek	21 ms average
Index Pulse Period	8.3 ms (nominal)
Average Latency	4.2 ms (nominal)
Rotational Speed	7200 RPM (nominal)
Data Transfer Rate (Buffer to Host)	100 MB/s (Mode 5 Ultra ATA) 66.6 MB/s (Mode 4 Ultra ATA) 33.3 MB/s(Mode 2 Ultra ATA) 16.6 MB/s (Mode 4 PIO) 16.6 MB/s (Mode 2 multi-word DMA)
Transfer Rate (Buffer to Disk)	525 Mbits/s maximum
Interleave	1:1
Buffer Size	2 MB
Spindle Start Time From Power-on to Drive Ready	7.0s average 9.0s maximum
Spindle Start Time From Power-on to Rotational Speed	5.0s average 7.0s maximum
Spindle Stop Time	6.5s average
Contact Start/Stop Cycles (CSS)	50 000 minimum