A B - 1 4 0 WESTERN DIGITAL
NO MORE PRODUCED Native| Translation
------+-----+-----+-----
Form 2.5"/SUPERSLIMLINE Cylinders 1390| 980| |
Capacity form/unform 42/ MB Heads 2| 5| |
Seek time / track 16.0/ 5.0 ms Sector/track | 17| |
Controller IDE / AT Precompensation
Cache/Buffer 32 KB SEGMENTED Landing Zone
Data transfer rate 1.250 MB/S int Bytes/Sector 512
4.500 MB/S ext
Recording method RLL 2/7 operating | non-operating
-------------+--------------
Supply voltage 5 V Temperature *C 5 55 | -40 65
Power: sleep 0.5 W Humidity % 8 85 | 5 95
standby 0.5 W Altitude km 2.600| 12.000
idle 1.3 W Shock g 10 | 100
seek W Rotation RPM 3383
read/write 2.4 W Acoustic dBA 36
spin-up W ECC Bit 56
MTBF h 100000
Warranty Month 24
Lift/Lock/Park YES Certificates CSA,FCC,IEC950,UL1950,VDE
**********************************************************************
L A Y O U T
**********************************************************************
WESTERN WDAB130/AB140/AH260/AH280 TECHNICAL REFERENCE MANUAL
---+43---------------J1-----------------------1---7-5-3-1-+-----
|o o o o o o o o o o o o o o o o o o o o o o . o o o o |J2
|o o o o o o o o o o o o . o o o o o o o o o . o o o o |
44----------------------20-----------------2---8-6-4-2-+
**********************************************************************
J U M P E R S
**********************************************************************
WESTERN WDAB130/AB140/AH260/AH280 TECHNICAL REFERENCE MANUAL
Jumper Setting
==============
Single Drive
------------
--+7-5-3-1+
|o o o o|
|o o o o| J2
--+8-6-4-2+
The drive have a jumper block (J2 located next to the 44-pin
connector on the drive. If you are installing the drive as the only
intelligent drive in the system, you do not need to install jumpers
on the J2 connector. This is considered a standard single drive
installation, and no jumpers are required. Note that even with no
jumper installed, the drive checks the DRIVE ACTIVE/SLAVE PRESENT
(DASP) signal to determine if a slave intelligent drive is present.
Dual Installation
-----------------
If you have a dual installation (two intelligent drives), you must
designate one of the drives as the master and the other as the slave
drive. The jumper pins on the J2 connector need to be configured for
the dual installation.
Master Drive
------------
--+7-5-3-1+
|o o X o| J2
|o o X o|
--+8-6-4-2+
To designate the drive as the master, place a jumper shunt on pins
3-4. When configured as the master drive, the drive assumes that a
slave drive is present. The jumper on pins 3-4 is optional if the
slave drive follows the same protocol (Common Access Method AT Bus
Attachment) as the master.
Dual installations require a master/slave drive configuration, where
one drive is designated as the primary (master) drive and the other
is designated as the secondary (slave) drive. The drives are
compatible in dual installations with other intelligent drives that
support a master/slave configuration.
Slave Drive
-----------
--+7-5-3-1+
|o o o X|
|o o o X| J2
--+8-6-4-2+
To designate the drive as a slave, place a jumper shunt on pins 1-2.
When configured as the slave drive, the drives delay spin up for four
seconds after powerup reset. This feature prevents overloading of the
power supply during powerup.
Reserved
--------
--+7-5-3-1+ --+7-5-3-1+
|o X o o| |X o o o|
|o X o o| J2 |X o o o| J2
--+8-6-4-2+ --+8-6-4-2+
**********************************************************************
I N S T A L L
**********************************************************************
WESTERN WDAB130/AB140/AH260/AH280 TECHNICAL REFERENCE MANUAL
Notes on Installation
=====================
Orientation
-----------
The drives can be mounted in many different ways depending upon the
physical design of your system.
Screw Size Limitations
----------------------
The drive is mounting to the chassis using four M3 x .5-6H screws
from the bottom or from the side.
Caution: Screws which are too long will damage board components. The
side mounting screws must engage no mre than .125 inch. The bottom
mounting screws must engage no more than .17 inch.
Connector
---------
The drives connect directly to an industry-standard 44-pin IDE Inter-
face connector.
Intelligent Drive
-----------------
The drives do not require a slot-mounted controller card since the
controller circuitry and 44-pin connector are already mounted on the
drive.
Grounding
---------
The mounting screws connect the head disk assembly and the printed
circuit board to the system chassis ground. Therefore, no external
grounding strap is required.
**********************************************************************
F E A T U R E S
**********************************************************************
WESTERN WDAB130/AB140/AC260/AC280 TECHNICAL REFERENCE MANUAL
General Description
-------------------
Western Digital's Tidbit I Series and Tidbit II Series drives are
high-performance, 2.5-inch intelligent drives for portable, AT-
compatible personal computers.
The Tidbit I and II drives include advanced, reduced-power operating
modes to extend battery life. The drives have an average seek time of
sub-16ms, and including CacheFlow(TM), Western Digital's adaptive,
multi-segmented, 32-Kbyte caching system. CacheFlow constantly
evaluates the size of the data request and the type, whether random
or repetitive, and adapts to the optimum caching method to provide
maximum system throughput.
Automatic Head Parking
----------------------
Head parking is automatic. On powerdown, the drive heads retract to
safe, non-data landing zone and lock into position, thus protecting
data integrity.
Preparing the Drive for Use
---------------------------
The drives are preformatted (low-level) at the factory and come
equipped with a full complement of defect management characteristics.
No modifications are required before installation. If at some later
time you need to perform defect mapping, contact Western Digital
Technical Support for information on the WDAT_IDE utility management.
Embedded Sector Servo Control
-----------------------------
These drives feature an embedded sector servo concept to provide
sampled, position feedback information to the head position servo
system. The embedded information precedes each data sector and
provides position updates on a sector by sector basis. This high
sampling rate supports the high-frequency servo bandwidth required
for fast access times as well as highly accurate generation of servo
feedback information without requiring the full data surface
required by a dedicated servo control concept.
Translation
-----------
The drives provide a linear disk address translator to convert
logical sector addresses to physical sector addresses to ensure
compatibility with any drive setup parameter.
Error Recovery
--------------
The drives use a 56-bit Error Correction Code (ECC) for automatic
detection and correction of errors in the data field.
Guaranteed Compatibility
------------------------
Western Digital performs extensive testing in its Functional
Integrity Testting Labs (FIT Lab(TM)) to ensure compatibility to all
AT-compatible computers and standard operating systems.
Zoned Recording
---------------
The drives employ zoned recording to increase the data density on the
outer tracks of the drive. The outermost tracks contain 40 percent
more sectors than the innermost tracks, thereby increasing the total
capacity of the drive.
Buffer RAM
----------
A 32-Kbyte static RAM buffer enhances data throughput by buffering
sector data between the drive electronics and the system bus. The RAM
only buffers read/write data and ECC information. The buffer is
accessed by two channels, each having a separate 15-bit address and
byte-count register. The channels operate simultaneously, accepting
read and write operations from two data paths. The address access
time for the buffer RAM is 120 ns (maximum).
Air Filtration System
---------------------
It is absolutely essential that air circulating within the drive be
particle free. The HDA is assembled in a Class 100 purified air
environment, and then sealed with tape. To retain this clean
environment, the drive is equipped with two filters. One filter, the
recirculating filter, cleans the air within the HDA. The
recirculating filter traps any particulates which may be generated
during spindle start and stop operations. Mounting the recirculating
filter next to the disk places the filter in the direction of the air
flow. This strategic placement of the filter allows the rotating
disks to act as an air pump forcing air through the recirculating
filter. A second filter, the breather filter, cleans any external air
entering the HDA. The breather filter also equalizes the internal and
external air pressure. The breather filter is located on the bottom
of the HDA.
Defect Management
-----------------
Every drive undergoes factory-level intelligent burn-in, which
troughly tests for any defective sectors on the media before the
drive leaves the manufacturing facility. Following he extensive
tests, a primary defect list is created. This list contains the
sector, cylinder, and head numbers for all defects. The purpose of
the sector/track map is to manage the reallocation of spare sectors
and tracks after they have been assigned.
Translation
-----------
The drives implement linear address translation. The translation mode
and translated drive configuration are selected by using the Set
Drive Parameters command to issue head and sector/track counts to the
translator. The product of the cylinder, head, and sector/track
counts must be equal to or less than the maximum number of sectors
available to the user. The maximum number of sectors per drive for
the AB130 and AB140 drives are 63,475 and 83,564 sectors,
respectively. The maximum number of sectors per drive for the AH260
and AH280 are 123,546 and 167,130 sectors, respectively. Each sector
consists of 512 bytes.
The minimum value for any translation parameter is one. The maximum
value for any translation parameters is as follows:
Sector/track (SPT) 63
Heads 16
Cylinder 1024
The values in the Sector Count Register and the SDH Register
determine the sectors per track (SPT) and heads. Regardless of the
values of the SPT and the heads, the drive is always in the
translation mode.
**********************************************************************
G E N E R A L
**********************************************************************
WESTERN TIPS
WESTERN DIGITAL 3.5-INCH DRIVES FREQUENTLY ASKED QUESTIONS
----------------------------------------------------------
1) Will a Caviar drive work in my system?
If your computer is 100% AT compatible and has either a 40-pin AT
IDE interface on the motherboard or an IDE controller card with a
40-pin data cable.
2) What are the master/slave jumper settings on Western Digital
drives?
All Western Digital drives are configured the same. On the back of
the drive between the 4-pin power connector and the 40-pin data
connector, there is a jumper block J8 consisting of 6 pins.
Western Digital hard drives are shipped with a jumper shunt in the
neutral storage position (across pins 5 and 3) for future dual
drive use.
- If you are installing the Western Digital hard drive as the only
hard drive in your system, leave the jmper shunt in the neutral
storage posiition. Jumper shunts are not required for single hard
drive installations.
- To designate the Western Digital hard drive as the master (C:),
place a jumper shunt on pins 5-6
- To designate the Western Digital hard drive as the slave (D:),
place a jumper shunt on pins 3-4.
3) What are the drive type and the drive parameters in the CMOS, for
Western Digital drives?
On top of the drive, the number of cylinders, heads and sectors
per track are printed on the label. Precomp and L-zone should be
set equal to the drive's cylinder count + 1. Select user type or
custom type (typically type 41 or 42) for your drive. This will
allow you to type in the parameters. Older systems that do not
offer a user type can either upgrade the system BIOS or set the
drive to drive type 1 (which should be a smaller drive size), and
run Ontrack Disk Manager from A drive to get the full capacity of
the drive. If you do not follow one of these procedures and your
system is pre-1994, you will be limited to the largest size drive
your BIOS will allow.
4) What is the Ontrack Disk Manager software that came with my drive
and what does it do?
Ontrack Disk Manager is the original hard disk installation
package that will initialize, partition, and prepare your hard
drive for use. Ontrack Disk Manager also allows you to access the
full capacity of the drive even when your system BIOS can't. It is
compatible with 32-bit disk access.
Note: Ontrack Disk Manager must be installed from floppy drive A. If
your A drive is a 5.25-inch floppy drive, copy the contents of your
Ontrack Disk Manager disk to a formatted 5.25-inch disk and re-run
Ontrack Disk Manager.
5) I just installed Ontrack Disk Manager on my Caviar drive and tried
to install DOS. DOS attempted to write to my drive and it
formatted my drive back to 528 MB which is my BIOS limitation. How
do I install DOS and still get the full capacity of my drive?
After Ontrack Disk Manager installation, you must create an
Ontrack Disk Manager rescue disk. There are two ways of
accomplishing this:
OPTION 1:
- Create a clean DOS bootable disk.
- Copy 2 files from the Ontrack Disk Manager disk to your bootable
disk: XBIOS.OVL, and DMDRVR.BINs Create a CONFIG.SYS file on this
bootable disk with these 3 lines: DEVICE=DMDRVR.BIN FILES=35
BUFFERS=35
- Remove the floppy and reboot the system.
- When you see the message "Press spacebar to boot from diskette",
press the spacebar (system halts).
- Insert the rescue disk in the A: drive.
- Press any key (system resumes boot process).
- At the A: prompt, remove rescue disk, insert DOS installation disk
and type SETUP.
- You can now install DOS without overwriting the Ontrack Disk
Manager files.
OPTION 2:
- Create a clean DOS bootable disk.
- Insert Ontrack Disk Manager disk in the A: drive.
- At the A prompt, type: DMCFIG/D=A:. You will be prompted to insert
a bootable floppy in the A: drive.
- Follow the prompts on the screen. Ontrack Disk Manager will ask you
to change disks a few times.
- Continue until Ontrack Disk Manager is finished.
- Remove the floppy and reboot the system.
- When you see the message "Press spacebar to boot from diskette".
Press the spacebar (system halts).
- Insert the rescue disk in A drive.
- Press any key (system resumes boot process).
- At A prompt, remove rescue disk, insert DOS installation disk and
type SETUP.
- You can now install DOS without overwriting the Ontrack Disk
Manager files.
6) CHKDSK or SCANDISK reports a few bad sectors. How do I go about
fixing the problem.
You can use the Western Digital defect management utility WDATIDE.
One of its options is the comprehensive surface analysis. This
procedure will mark all grown defects bad if indeed there are any
and it will compensate for the lost capacity by utilizing spare
tracks.
Note: This utility is data destructive. Back up all data on the drive
before using it. Due to the thoroughness of this operation, WDATIDE
can take quite a bit a time depending on the capacity of your drive.
7) Do I have to do anything with my original drive when adding a new
drive to my system?
Yes, one hard drive must be designated as the master drive
(preferably the newer, faster drive) and the other must be
designated as the slave drive. Typically, most drives need to have
a jumper placed on them to specify the Master or Slave position.
For information on non-Caviar hard drives, please contact the
appropriate manufacturer.
8) I installed my new drive and entered the drive parameters in the
CMOS, but the drive will not boot or it displays the message "HDD
controller failure."
Your drive must be partitioned and formatted before it will be
bootable. If your system will support drives larger than 528 MB,
and you have a copy of MS-DOS or PC-DOS version 5.0 or greater,
insert the setup diskette in your floppy drive and turn on your
computer. Follow the prompts and DOS will partition and format the
drive for you.
If you do not have a copy of MS-DOS or PC-DOS version 5.0 or greater,
you will need to boot from a bootable disk and then run the FDISK
command to partition your drive, and then format the drive using the
DOS FORMAT command. After running format, you should be able to
reboot your computer from your hard drive.
9) How can I use the full capacity of my Caviar drive of 540 MB or
greater?
You can use Ontrack Disk Manager to obtain full capacity if your
system does not support LBA mode. If your system does support LBA
mode, you can enable LBA in your CMOS setup utility.
10) How can I get 32-Bit Disk Access in Windows on my Caviar AC2540,
AC2700 or AC31000 in Windows 3.1x? If your BIOS supports the
drive at full capacity (i.e., the BIOS supports Logical Block
Addressing) you use WDCDRV.386, Western Digital's FastDisk device
driver. This driver is contained in a file named WIN31.EXE
available for downloading from our bulletin board (714/753-1234),
our Web server (WWW.WDC.COM), our FTP site (FTP.WDC.COM), our
forum on the Microsoft Network (Go word WDC), and our forum on
America On-line (keyword WDC). If your BIOS does not support LBA
mode and you have installed your drive using Ontrack Disk Manager
(v6.03 and above), run DMCFIG to install WDCDRV.386 and obtain
32-Bit Disk Access.
11) My drive will not spin up or spins down after a few seconds.
This is a drive failure. Return the drive to the distributor or
contact a technical support representative to receive a Return
Materials Authorization (RMA).
12) CMOS, FDISK and File Manager in Windows report less than the
capacity of my new drive, but CHKDSK reports the right number of
bytes. Which is correct?
Setup (CMOS) and FDISK use a binary definition of a megabyte
which is calculated at 1,048,256 bytes per megabyte. All hard
drive manufacturers and the DOS CHKDSK utility use a decimal
definition of a megabyte which is calculated at 1,000,000 bytes
per megabyte. This is why some utilities show 515 MB for a 540
megabyte drive and some show the actual number.
13) How Can I install OS/2 for Windows, OS/2 3.0 WARP, Windows NT
3.5x or Windows 95 on my drive which was initially installed
using Ontrack Disk Manager?
If you have Ontrack Disk Manager version 6.03, 6.03a, or 6.03b,
download the file named DMPATCH.EXE from Western Digital's online
services: ftp site: ftp.wdc.com
World Wide Web Site: http://www.wdc.com/
Microsoft Network (MSN) - Go word WDC
America Online (AOL) - Keyword: Western Digital
Western Digital's BBS at (714) 753-1234
This file has the latest Ontrack Disk Manager drivers which will
allow you to install OS/2 version 2.1x, OS/2 WARP, Windows NT 3.5x
or Windows 95 on your hard drive. Please read the included readme
file with this file for further detail.
14) My drive will work as a slave but not as a master (or vice-
versa).
Check master/slave jumpers on all drives. Also, some drive's speed
and timing differ drastically as to the initial spinup sequence. This
might confuse the system and cause one of the drives not to be
recognized. The best solution for this situation is to exchange
drives (make the master a slave and vice-versa).
15) My drive will not partition when I run FDISK. It hangs the system
or it displays the message: "Runtime error."
This is usually caused by corruption or damage to track zero. Use
the Western Digital utility WDFMT to format the drive. If that
does not help, call Western Digital Technical support at
1-800-ASK-4-WDC to get further instructions.
16) Can a hard drive be mounted on it's side, edge, or upside down?
Drives can be mounted on any side but it is preferable to mount
the drive right side up. It is also important to use all four
screws to hold the drive firmly in place.
Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.)
----------------------------------------------------------------
S.M.A.R.T. enables a drive's internal status to be monitored through
diagnostic commands at the host level.
The Caviar AC21600, AC32100 and AC32500 drives monitor read error
rate, start/stop count, spin-up retry count, and drive calibration
retry count. All of these attributes are updated and stored on the
hard drive in the reserved area of the disk. The hard drive also
stores a set of attribute thresholds that correspond to the
calculated attribute values. Each attribute threshold indicates the
point at which its corresponding attribute value achieves a negative
reliability status.
====================================================================
QUESTION
Which hard drive specification is most important to overall
system performance ?
- Host Transfer Rate
- Drive RPM (revolutions per minute)
- Disk Transfer Rate (Media Rate)
- Seek Time
- Cache Size
- PC Data Handling
- All of the above
Answer
The correct answer is actually a combination of "all of the above,"
keeping in mind most of the above specifications are interrelated
when it comes to optimizing system performance.
The pie chart illustrates the relative influence of factors affecting
drive performance during a typical random I/O operation (reading
and writing to a hard drive).
The major determinate of hard drive performance is mechanical
factors which are one hundred times slower than the high-speed
electronics contained in a drive.
Factors Affecting Hard Drive Performance
(In their relative order of importance)
MECHANICAL LATENCIES
Mechanical Latencies include both Seek Time and Rotational
Latency. The seek time is a measure (in milliseconds) of how
fast the hard drive can move its read/write heads to a desired
location. Rotational latency is a measure of the average time
(also in milliseconds) the read/write heads must wait for the
target sector on the disk to pass under them once the read/write
heads are moved to the desired target track.
Mechanical latencies are the main hindrance to higher performance
in modern Enhanced IDE (EIDE) hard drives. The time delays of
mechanical latencies are one hundred times higher than
electronic (non-mechanical) latencies associated with the
transferring of data. Therefore, reducing mechanical latencies
(a lowering of seek time and rotational latency) should be the
top consideration in improving hard drive performance.
RPM
This is the rotational speed of the media (disk), also referred
to as the spindle speed. Hard drives only spin at one constant
speed. Typical speeds are 3600 to 3880, 4500, and 5200 to 5400
revolutions per minute. The slower the RPM, the higher the
Mechanical Latencies. Disk RPM is a critical component of hard
drive performance because it directly impacts the rotational latency
and the Disk Transfer Rate explained below.
DISK TRANSFER RATE
The Disk Transfer Rate (sometimes called media rate) is the
speed at which data is transferred to and from the disk media
(actual disk platter) and is a function of the recording frequency.
Typical units are bits per second (BPS), or bytes per second.
Modern hard disks have an increasing range of Disk Transfer
Rates from the inner diameter to the outer diameter of the disk.
This is called a "zoned" recording technique.
The key media recording parameters relating to density per platter
are Tracks Per Inch (TPI) and Bits Per Inch (BPI). A track is a
circular ring around the disk. TPI is the number of these tracks
that can fit in a given area (inch). BPI defines how many bits
can be written onto one inch of a track on a disk surface. To
greatly simplify, the Disk Transfer Rate (the rate at which data
is read and written to the disk) is dependent upon the speed of
the disk (RPM) and the density of the data on the disk (BPI).
Even most modern, high-speed, 5000 RPM hard drives are generally
limited to a maximum Disk Transfer Rate of approximately 9 to 10
MB per second. This specification is critical to performance and
must be weighed carefully against such electronic latencies as
Mode 3 PIO and Mode 4 PIO host transfer rates explained below.
PC DATA HANDLING
After the data moves down the IDE cable from the drive to the host
interface, there are several factors that can affect drive
performance over which the hard drive has no control. PC Data
Handling is independent from the hard drive and very dependent
upon the CPU type and speed, the BIOS overhead (how the system
issues commands to the hard drive), speed and size of the system
RAM and RAM cache, CPU-to-memory speed, and storage subsystem
performance. PC Data Handling is also affected by the caching
methods of such software applications as SMARTDRIVE, 32-bit
disk access operating system drivers, etc.
HOST TRANSFER RATE
The speed at which the host computer can transfer data across the
IDE or EIDE interface. Processor Input/Output (PIO) modes and
Direct Memory Access (DMA) modes are defined in the ATA-2 industry
specification as follows:
Mode 3 PIO 11.1 MB/sec
Mode 4 PIO 16.6 MB/sec
Mode 1 DMA 13.3 MB/sec
Mode 2 DMA 16.6 MB/sec
Modern host computer systems usually support most of the above
modes. Faster Host Transfer Rates in the future will use multi-word
DMA modes as the industry will not support any future PIO mode
standards beyond mode 4.
The computer system manufacturer is responsible for implementing a
Host Transfer Rate that is high enough to ensure that the host
computer is not the performance bottleneck. Implementing
increasingly higher Host Transfer Rates without corresponding
increases in Disk Transfer Rates on the hard drive will not result
in increased drive performance.
Cache Buffer Size - Is Bigger Always Better ?
A Cache Buffer is similar to a water glass. When you are writing
to a hard drive, the host computer fills the glass and the disk
media empties it. If you are reading data from a hard drive, the
disk media fills the glass and the host computer empties it.
The reason that a bigger cache buffer is not always better
(or faster) is because the host computer (with Mode 4 PIO or
Mode 2 DMA capabilities) can empty or fill the glass much faster
than the hard drive can empty or fill it. When the host system can
transfer data in or out of the cache buffer faster than the media
rate, a larger buffer size becomes irrelevant because the host
system is always "waiting" for the hard drive.
Western Digital hard drives are designed with cache buffer sizes
that are matched to the Disk Transfer Rate capabilities of the
drive and the Host Transfer Rates of modern computer systems. All
of our drives are benchmarked with various cache buffer sizes to
verify that the most cost-effective and performance-effective
cache size is implemented.
Confusion Over Mode 4 and Mode 2 DMA
The Enhanced IDE program created the long-range road map for
performance enhancements which included faster disk and host
transfers, Mode 3, Mode 4, Mode 2 DMA, etc. Currently, computer
systems and hard drive controller silicon have most of the elements
needed to implement Mode 4 PIO or Mode 2 DMA (a 16.6 MB/sec Host
Transfer Rate). However, to take advantage of these performance
modes, physical drive architecture must also make some performance
improvements in the area of Mechanical Latencies and Disk Transfer
Rate (media rate) as defined earlier.
Some competitors, in their eagerness to supply a new feature, are
prematurely marketing Mode 4 and Mode 2 DMA. While their drive
controller silicon supports these modes (which is very easy and
inexpensive to implement), spindle speeds (RPM), rotational latency,
bit density, and other factors have not yet been improved (these
being very difficult and costly). The result is hard drives which
have the electronic capability to do Mode 4 and Mode 2 DMA transfer
rates, but can't take advantage of these modes due to the slower
Disk Transfer Rate of the drive.
Western Digital will not be implementing Mode 4 or Mode 2 DMA on
older drive products as the host systems into which these drives
are designed are not electrically capable of these data transfers,
nor are the Disk Transfer Rates on these drives beyond current Mode
3 capabilities. As next generation systems are introduced, they will
be paired with next generation drives. Those drives will require
and offer true Mode 4 / Mode 2 DMA capability from a total drive
architecture standpoint.
=====================================================================
AC2540/2635/2700/2850/21000/31000/31200/31600
Windows 95 Operating System Addendum
------------------------------------
The information in this addendum supersedes that supplied in Windows
95 section on pages 35 and 36 of this manual. Please refer to thos
addendum for Windows 95 questions.
Although Windows 95 is capable of recognizing the full capacity of
hard drives larger than 528 MB in systems with a translating BIOS,
some restrictions apply to systems without a translating BIOS.
For Systems With a Translating BIOS
-----------------------------------
Enter your CMOS setup and select a drive type that will recognize the
full capacity of your drive. This is usually done by selecting the
auto config drive tape. The boot partition can be set up to be as
large as the full capacity of your hard drive.
For Systems Without a Translating BIOS
--------------------------------------
Enter your CMOS setup and select a user defined drive type. Enter
these parameters: cylinders = 1024, heads = 16, sectors = 63. Your
system's total disk space will be limited to a maximum of 528MB.
If you want your system to utilize more than 528 MB of disk space,
you must use Ontrack's Disk Manager software (or a similar third-
party installation software).
Installing Windows 95 on a Hard Drive with Ontrack Disk Manager
Already Installed
---------------------------------------------------------------
The Windows 95 installation program will analyze your computer
system and install seamlessly with Ontrack Disk Manager.
Computer Systems with Windows 95 Already Installed
--------------------------------------------------
If you are installing a Western Digital hard drive and Ontrack Disk
Manager on a computer system with Windows 95 already installed, you
must install Ontrack Disk Manager as described here.
Enter your CMOS setup and select a user defined drive type. Enter
these parameters for drives with capacities over 528MB:
Cylinders = 1024, Heads = 16, Sectors = 63.
Save these changes and reboot your computer.
1. Select the Start icon from the Windows 95 main screen.
DO NOT open an MS-DOS menu from Win 95 to install Ontrack Disk
Manager.
2. Choose the Shut Down option.
3. Select Resatrt Computer in DOS mode. When your computer restarts,
you should be at the DOS prompt.
4. Install Ontrack Disk Manager.
Windows 95 will noe recognize the full capacity of your hard drive
and run in 32-bit disk access mode for optimum performance.