Western Digital 2GB/4GB 7200 RPM Enterprise Drive Specifications
Power Computing provided the information in this article and it was deemed accurate as of 14 November 1997. Apple Computer, Inc. is not responsible for its content. This article is being provided as is and will not be updated in the future.
WD Enterprise, 2.1 and 4.3 Gigabyte SCSI Hard Drives
WD Enterprise drives -- the first in a family of 7200 RPM drives -- deliver outstanding performance, capacity, and reliability, and are an excellent choice for audio-video, workstation, server, multi-user, and array applications.
These drives feature formatted capacities of 2.1 GB and 4.3 GB with host data transfer rates of up to 40 MB/s. They are compliant with SCSI-3 SPI, support Ultra Fast and Ultra Fast Wide host data transfers, and offer a SCA-2 interface. Advanced caching, command queuing, S.M.A.R.T. (Self Monitoring and Reporting Technology), and S.C.A.M. (SCSI Configure AutoMagically) are standard features of WD Enterprise drives.
WD Enterprise drives incorporate the mechanical platform design and proven recording technologies of Western Digital's award-winning WD Caviar drives. This quality design means WD Enterprise drives have fewer heads and disks in comparison to competitive drives, significantly reducing the drives' components. Fewer components results in higher reliability -- placing WD Enterprise drives a step ahead of our competition.
Fewer disks and heads also means less head switches, which combined with an 8 ms seek time, up to 140 Mb/s media data rate, and a low 4.17 ms rotational latency (7200 RPM) gives WD Enterprise drives unique performance advantages over our competition.
WD Enterprise drives deliver the performance, capacity, and reliability demanded by all high-performance enterprise systems.
Features
High Performance -- WD Enterprise drives have a 7200 RPM spindle speed, 8 ms average seek time, 512 KB or 1 MB cache option (Power Computing uses drives with a 512KB Cache), are compliant with SCSI-3 SPI, and support for Ultra Fast and Ultra Fast Wide host transfers. The advanced caching, command queuing (with seek and latency optimization) for multi-threaded workloads, embedded servo (uninterrupted data stream), and 140 Mb/s maximum media data rate yield superior performance.
Highest Disk Capacity -- Capacities over 1 GB per disk are made possible by using the proven technology of advanced thin-film heads and a PRML read channel. These drives are available in 2-disk (2.1 GB) and 4-disk (4.3 GB) versions.
Superior Quality and Reliability -- Fewer disks and heads translate into many performance and reliability advantages compared to our competition. These high performance drives are based on a Western Digital design platform and process that has already achieved world-class quality. 1 million hours MTBF means years of maintenance-free operation.
Low Power -- An efficient electrical design decreases power requirements to as low as 5 watts at idle.
MODEL WDE2170 WDE4360
------------------ -------------------------- -----------------
Form Factor 3.5-inch 3.5-inch
Formatted Capacity 2170 MB(1) 4360 MB(1)
Interface Ultra Fast (50-pin) Same as WDE2170
Ultra Fast Wide (68-pin)(2) Same as WDE2170
Average Seek Time 8 ms(3) 8 ms(3)
Data Transfer Rate:
Media to Buffer 81 - 140 Mb/s max 81 - 140 Mb/s max
Buffer to Host 40 MB/s max 40 MB/s max
Spindle Speed 7,200 RPM 7,200 RPM
Buffer 512 KB Standard 512 KB Standard
MTBF 1,000,000 POH 1,000,000 POH
Notes:
(1) Western Digital defines a megabyte (MB) as 1,000,000 bytes, and a gigabyte (GB) as 1,000,000,000 bytes. (2) Differential interface options available on 68-pin models. (3) Average Read Seek Time is determined by dividing the total number of these ordered pairs at nominal environmental conditions.
Termination Jumpers
To ensure reliable communication, the SCSI bus must be properly termi-nated. Devices located at the physical ends of the SCSI bus should have their terminators enabled. All other devices must have their terminators disabled. Option block pins 23 and 24 are dedicated to the SCSI Termination option. To enable SCSI termination, install a jumper across paired pins 23 and 24. To disable SCSI termination, no jumper is required.
SCSI ID Jumpers
Each device on the SCSI bus requires a unique SCSI ID number (0 to 7 for 8-bit devices, 0 to 15 for 16-bit devices). Option block pins 1 through 8 are used to set the SCSI IDs. Refer to Table 1 for a complete matrix of jumper settings. The host computer's SCSI controller typically uses ID number 7, and the other numbers are used for devices such as hard drives. The WD Enterprise drive has a default SCSI ID of 0.
l jumper installed @ jumper removed = legal 8-bit bus IDs*
* If any device on your computer's SCSI bus supports only 8-bit SCSI IDs, the WD Enterprise drive must be set to one of these values. When setting IDs on 50-pin drives, pins 7 and 8 are not used.