Intel AN430TX - Motherboard - ATX Technical manual

AN430TX
Motherboard
Specification Update
Release Date: September 1998
Order Number: 674301-016
The AN430TX motherboard may contain design defects or errors known as errata which may
cause the product to deviate from published specifications. Current characterized errata are
documented in this Specification Update.

Information in this document is provided in connection with Intel products. No license, express or implied, by estoppel or
otherwise, to any intellectual property rights is granted by this document. Except as provided in Intel’s Terms and Conditions of
Sale for such products, Intel assumes no liability whatsoever, and Intel disclaims any express or implied warranty, relating to
sale and/or use of Intel products including liability or warranties relating to fitness for a particular purpose, merchantability, or
infringement of any patent, copyright or other intellectual property right. Intel products are not intended for use in medical, life
saving, or life sustaining applications.
Intel retains the right to make changes to specifications and product descriptions at any time, without notice.
The AN430TX motherboard may contain design defects or errors known as errata which may cause the product to deviate from
published specifications. Current characterized errata are available on request.
Contact your local Intel sales office or your distributor to obtain the latest specifications before placing your product order.
* Third party brands and names are the property of their respective owners.
Copies of documents which have an ordering number and are referenced in this document, or other Intel literature, may be
obtained from:
Intel Corporation
P.O. Box 5937
Denver, CO 80217-9808
or call in North America 1-800-548-4725, Europe 44-0-1793-431-155, France 44-0-1793-421-777,
Germany 44-0-1793-421-333, other Countries 708-296-9333
Copyright 1998, Intel Corporation

CONTENTS
REVISION HISTORY ...............................................................................................................................v
PREFACE...............................................................................................................................................vi
Specification Update for AN430TX Motherboards
GENERAL INFORMATION ......................................................................................................................3
SPECIFICATION CHANGES ...................................................................................................................9
ERRATA.................................................................................................................................................10
SPECIFICATION CLARIFICATIONS......................................................................................................16
DOCUMENTATION CHANGES .............................................................................................................18

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AN430TX SPECIFICATION UPDATE
v
REVISION HISTORY
Date of Revision Version Description
May 1997 -001 This document is the first Specification Update for the Intel®
AN430TX motherboard.
June 1997 -002 Added Specification Change 1, Specification Clarifications 1-3 and
Documentation Changes 1-3.
July 1997 -003 Added Erratum 4, Specification Clarification 4 and Documentation
Changes 4-9.
August 1997 -004 Updated Documentation Changes 1 and 7-8. Added Specification
Clarification 5 and Documentation Change 10.
September 1997 -005 Updated Documentation Change 10. Added Errata 5 and 6.
October 1997 -006 Updated Erratum 3. Added Errata 7-10 and Documentation
Change 11.
November 1997 -007 Updated Errata 9-10 and Documentation Change 11. Added
Erratum 11 and Documentation Changes 12-13.
December 1997 -008 Added Erratum 12 and Specification Clarifications 6-7.
January 1998 -009 Added Errata 13-14 and Specification Clarification 8.
February 1998 -010 Added Erratum 15.
April 1998 -011 Added Erratum 16 and Documentation Change 14.
May 1998 -012 Added Errata 17-18. Updated Errata 5, 13 and 16.
June 1998 -013 Added Documentation Change 15.
July 1998 -014 Added Erratum 19 and Documentation Change 16. Updated
status of Erratum 16.
August 1998 -015 Added Erratum 20.
September 1998 -016 Added Erratum 21. Updated status of Erratum 20.

AN430TX SPECIFICATION UPDATE
v
i
PREFACE
This document is an update to the specifications contained in the AN430TX Motherboard Technical Product
Specification
(Order Number 282955). It is intended for hardware system manufacturers and software
developers of applications, operating systems, or tools. It will contain Specification Changes, Errata,
Specification Clarifications, and Documentation Changes.
Refer to the
Pentium

Processor Specification Update (Order Number 242480) for specification updates
concerning the Pentium processor. Items contained in the
Pentium Processor Specification Update that
either do not apply to the AN430TX motherboard or have been worked around are noted in this document.
Otherwise, it should be assumed that any processor errata for a given stepping are applicable to the Printed
Board Assembly (PBA) revision(s) associated with that stepping.
Refer to the
82430TX PCIset Specification Update (Order Number 297736) for specification updates
concerning the 82430TX PCIset. Items contained in the
82430TX PCIset Specification Update that either do
not apply to the AN430TX motherboard or have been worked around are noted in this document. Otherwise,
it should be assumed that any PCIset errata for a given stepping are applicable to the Printed Board
Assembly (PBA) revision(s) associated with that stepping.
Refer to the
82371AB PIIX4 Specification Update (Order Number 297738) for specification updates
concerning the 82371AB PIIX4. Items contained in the
82371AB PIIX4 Specification Update that either do
not apply to the AN430TX motherboard or have been worked around are noted in this document. Otherwise,
it should be assumed that any PCIset errata for a given stepping are applicable to the Printed Board
Assembly (PBA) revision(s) associated with that stepping.
Nomenclature
Specification Changes are modifications to the current published specifications. These changes will be
incorporated in the next release of the specifications.
Errata are design defects or errors. Characterized errata may cause the AN430TX motherboard’s behavior
to deviate from published specifications. Hardware and software designed to be used with any given Printed
Board Assembly (PBA) and BIOS revision level must assume that all errata documented for that PBA and
BIOS revision are present on all motherboards.
Specification Clarifications describe a specification in greater detail or further highlight a specification’s
impact to a complex design situation. These clarifications will be incorporated in the next release of the
specifications.
Documentation Changes include typos, errors, or omissions from the current published specifications.
These changes will be incorporated in the next release of the specifications.

Specification Update for
AN430TX Motherboards

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AN430TX SPECIFICATION UPDATE
3
GENERAL INFORMATION
Basic AN430TX Motherboard Identification Information
AA Revision PBA Revision 82430TX PCIset Stepping BIOS Revision Notes
672839-304 669379-304 A1 4A3NT0X0.86A.0042.P02 1, 2, 3, 4, 5
672839-305 669379-305 A1 4A3NT0X0.86A.0047.P03 1, 2, 3, 4, 5
672839-306 669379-306 A1 4A3NT0X0.86A.0047.P03 1, 2, 3, 4, 5
672839-307 669379-307 A1 4A3NT0X0.86A.0047.P03 1, 2, 3, 4, 5
672839-308 669379-308 A1 4A3NT0X0.86A.0062.P06 1, 2, 3, 4, 5
672839-309 669379-309 A1 4A3NT0X0.86A.0062.P06 1, 2, 3, 4, 5
680905-302 680904-302 A1 4A3NT0X0.86A.0047.P03 1, 2, 3, 4, 5
680905-303 680904-303 A1 4A3NT0X0.86A.0047.P03 1, 2, 3, 4, 5
680905-304 680904-304 A1 4A3NT0X0.86A.0062.P06 1, 2, 3, 4, 5
680905-305 680904-305 A1 4A3NT0X0.86A.0062.P06 1, 2, 3, 4, 5
NOTES:
1. The AA/PBA number is found on a small label on the component side of the board.
2. The 82430TX PCIset kit used on this PBA revision consists of two different components as follows:
Device Stepping S-Spec Numbers
82439TX A1 L238
82371AB B0 L23P
3. The following errata contained in the
82430TX PCIset Specification Update
(Order Number 297736) either do not apply to
the AN430TX motherboard or have been worked around in this PBA and/or BIOS revision: 1S, 2S. All other errata
associated with the PCIset apply to this PBA revision. For specific details of any erratum please refer to the
82430TX
PCIset Specification Update
.
4. The following errata contained in the
82371AB PIIX4 Specification Update
(Order Number 297738) either do not apply to
the AN430TX motherboard or have been worked around in this PBA and/or BIOS revision. All other errata associated
with the PCIset apply to this PBA revision. For specific details of any erratum please refer to the
82371AB
PIIX4-Specification Update
.
5. The following errata contained in Part I of the
PentiumProcessor Specification Update (Order Number 242480) either do
not apply to the AN430TX motherboard or have been worked around in this PBA and/or BIOS revision: 5, 7, 9-11, 13-14,
16-17, 29, 31, 34, 36-37, 39, 40, 46, 48-50, 58, 60-64, 66-67, 69, 71, all DP errata, all AP errata, all TCP errata. All other
errata in Part I may apply to this revision level of the motherboard, depending on the stepping of the processor or the
specific software that is being executed. Also, some of these errata apply only to motherboards being used in an
application development environment. For specific details of any erratum please refer to the
Pentium Processor
Specification Update.

AN430TX SPECIFICATION UPDATE
4
Summary Table of Changes
The following table indicates the Specification Changes, Errata, Specification Clarifications, or Documentation
Changes which apply to the AN430TX motherboard. Intel intends to fix some of the errata in a future revision
of the motherboard, and to account for the other outstanding issues through documentation or specification
changes as noted. This table uses the following notations:
CODES USED IN SUMMARY TABLE
Doc: Document change or update that will be implemented.
Fix: This erratum is intended to be fixed in a future revision of the motherboard or
BIOS.
Fixed: This erratum has been previously fixed.
NoFix: There are no plans to fix this erratum.
Shaded: This erratum is either new or modified from the previous version of the document.
NO. PLANS SPECIFICATION CHANGES
1 Doc Support for 233 MHz Pentiumprocessors with MMXtechnology
NO. PLANS ERRATA
1 NoFix System does not meet FCC Class B with unshielded USB cables
2 NoFix Audio driver does not support Windows* 3.x session within OS/2* Warp*
3 Fixed System BIOS does not recognize bootable USB devices
4 NoFix Video corruption or no video on boot
5 Fixed Memory decrease warning message not displayed
6 Fix Hard drive not detected on boot if user defined
7 Fixed Intel®EtherExpress™ Pro/100B fails to initialize with Windows 95
8 Fixed Potential battery drain if no AC power applied
9 Fixed LS-120 drive does not work as expected in Windows 95
10 Fix Serial mouse activity does not wake system after APM shutdown
11 Fix Stuck or depressed key during POST may cause system hang
12 Fixed Unable to define IDE heads value for secondary IDE hard drive in BIOS Setup
13 Fixed System BIOS may corrupt audio add-in card EEPROM
14 NoFix Windows 95 will not boot if LS-120 drive is only device on IDE channel
15 NoFix Advanced Power Management may suspend system during CD-ROM playback
16 Fixed BIOS does not correctly size 64 MB or larger DIMMs
17 Fixed System will not boot with network as first boot device
18 Fixed Unattended start feature does not require password before boot
19 Fixed System BIOS does not display user logo during POST

AN430TX SPECIFICATION UPDATE
5
NO. PLANS ERRATA
20 NoFix System using 3-mode floppy drive cannot read XDF format diskettes
21 NoFix System will not boot from ISA video adapter if Scan User Flash is enabled
NO. PLANS SPECIFICATION CLARIFICATIONS
1 Doc Advanced Power Management (APM) will not function as expected with Universal Serial Bus
(USB) enabled
2 Doc LS-120 drive and floppy will not function as expected for BIOS recovery
3 Doc PCI 2.1 Specification optional features
4 Doc Supervisor and user passwords
5 Doc Power supply considerations
6Doc LS-120 drive configured as a boot device
7Doc Resource allocation with all PCI slots used
8Doc Using shift print screen in BIOS Setup
NO. PLANS DOCUMENTATION CHANGES
1 Doc Revision of Section 1.6.1, “Main Memory”
2 Doc Addition of “Power On” section
3 Doc Revision of Section 5.1, “Specifications”
4 Doc Revision of Section 1.7.1, “82439TX System Controller (MTXC)”
5 Doc Revision of Section 1.12, “Add-In Board Expansion Connectors”
6 Doc Revision of Section 1.13.1, “Processor Configuration (J9C1-C, D)”
7 Doc Revision of Section 1.6.1.1, “EDO DRAM”
8 Doc Revision of Section 1.8.1, “Serial Ports”
9 Doc Revision of Section 1.13.3, “Clear CMOS (J9C1-A)”
10 Doc Revision of Section 1.16.1, “Power Supply Considerations”
11 Doc Revision of Section 3.1.12, “USB Support”
12 Doc Addition of “BIOS Beep Codes” section
13 Doc Revision of Section 3.1.4, “PCI IDE Support”
14 Doc Revision of video memory address
15 Doc Change to description of Manufacturing Options
16 Doc Addition of section describing real time clock

AN430TX SPECIFICATION UPDATE
6
The errata described in this specification update apply to combinations of PBA revision and BIOS revision as
shown in the table below. Descriptions of the individual errata referred to by number in the table below are
found in the ERRATA section of this document.
PBA Revision BIOS Revision Errata That Apply
669379-304 4A3NT0X0.86A.0042.P02 1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21
669379-305 4A3NT0X0.86A.0042.P02‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21
669379-306 4A3NT0X0.86A.0042.P02‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21
669379-307 4A3NT0X0.86A.0042.P02‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21

AN430TX SPECIFICATION UPDATE
7
PBA Revision BIOS Revision Errata That Apply
669379-308 4A3NT0X0.86A.0042.P02‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21
669379-309 4A3NT0X0.86A.0042.P02‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03‡1-3, 5-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1-2, 5-6, 8, 10-11, 14-15, 17-18, 20-
21
4A3NT0X0.86A.0082.P07 1-2, 6, 8, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 6, 8, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 6, 8, 10-11, 14-15, 20-21
680904-302 4A3NT0X0.86A.0042.P02‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1, 2, 4-6, 10-11, 14-15, 17-18, 20-21
4A3NT0X0.86A.0082.P07 1-2, 4, 6, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 4, 6, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 4, 6, 10-11, 14-15, 20-21
680904-303 4A3NT0X0.86A.0042.P02‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03 1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1, 2, 4-6, 10-11, 14-15, 17-18, 20-21
4A3NT0X0.86A.0082.P07 1-2, 4, 6, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 4, 6, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 4, 6, 10-11, 14-15, 20-21

AN430TX SPECIFICATION UPDATE
8
PBA Revision BIOS Revision Errata That Apply
680904-304 4A3NT0X0.86A.0042.P02‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1, 2, 4-6, 10-11, 14-15, 17-18, 20-21
4A3NT0X0.86A.0082.P07 1-2, 4, 6, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 4, 6, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 4, 6, 10-11, 14-15, 20-21
680904-305 4A3NT0X0.86A.0042.P02‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0047.P03‡1-7, 9-15, 17-18, 20-21
4A3NT0X0.86A.0062.P06 1, 2, 4-6, 10-11, 14-15, 17-18, 20-21
4A3NT0X0.86A.0082.P07 1-2, 4, 6, 10-11, 14-16, 18-21
4A3NT0X0.86A.0086.P08 1-2, 4, 6, 10-11, 14-16, 19-21
4A3NT0X0.86A.0088.P09 1-2, 4, 6, 10-11, 14-15, 20-21
NOTE:
‡ This combination of BIOS revision and PBA revision has not undergone regression testing. Use of a PBA with down-
revision BIOS is an untested combination and is undertaken at the user’s risk.

AN430TX SPECIFICATION UPDATE
9
SPECIFICATION CHANGES
The Specification Changes listed in this section apply to the AN430TX Motherboard Technical Product
Specification
(Order Number 282955). All Specification Changes will be incorporated into a future version of
that specification.
1. Support for 233 MHz Pentium

processors with MMXtechnology
Support for 233 MHz Pentiumprocessors with MMXtechnology is available in PBA revision 669379-304,
680904-302 and higher. Below are the jumper settings:
Processor
Freq. (MHz) Jumpers J9C1-C Jumpers J9C1-D Host Bus Freq. (MHz) PCI Bus Freq. (MHz) ISA Bus Freq. (MHz) Bus/Processor Freq. Ratio
100/233 5-6 1-2 and 4-5 66 33 8.33 1.5
NOTE:
There are no additional jumpering requirements for Pentium processors with MMX technology.
The 100 MHz Pentium processor and the 233 MHz Pentium processor with MMX technology have identical jumper
settings. The motherboard automatically detects which processor type is installed.

AN430TX SPECIFICATION UPDATE
10
ERRATA
1. System Does Not Meet FCC Class B with Unshielded USB Cables
PROBLEM:The motherboard will generate excessive electromagnetic radiation on unshielded USB cables,
even if no device or a low speed (sub-channel) USB device is attached to the cable.
IMPLICATION:The system will not meet FCC Part 15 Class B requirements when unshielded USB cable is
used. This is a violation of the USB v1.0 specification.
WORKAROUND:Use USB devices with shielded cable that meet the requirements for high speed (fully-rated)
USB devices.
STATUS:This erratum will not be fixed.
2. Audio Driver Does Not Support Windows* 3.x Session Within OS/2*
Warp*
PROBLEM:The AN430TX motherboard audio drivers for OS/2* Warp* or Windows* 3.x do not support audio
during a Windows 3.x session within OS/2 Warp.
IMPLICATION:No audio is available during a Windows 3.x session within OS/2 Warp. Normal audio support
will be available in native OS/2 Warp.
WORKAROUND:None.
STATUS:This erratum will not be fixed.
3. System BIOS Does Not Recognize Bootable USB Devices
PROBLEM:The system BIOS does not recognize a USB keyboard or mouse during a system boot. A USB
keyboard or mouse is not recognized until an operating system that supports USB is loaded.
IMPLICATION:1. The user is not able to use a USB keyboard to enter the BIOS Setup or to respond to error
messages that are displayed before an operating system with USB support is loaded.
2. The user is not able to use a USB keyboard or mouse with any operating system that does not have USB
support.
WORKAROUND:Use a standard PS/2* style keyboard and mouse in any configuration where input is
required before an operating system with USB support is loaded.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0062.P06.
4. Video Corruption or No Video on Boot
PROBLEM:An ATI* 264GTU device initialization problem will occur on power up when the power supply
ramping of the 3.3 V leads the 5.0 V by 5 ms or more. The 2.01 ATX Specification recommends that the
3.3 V DC rails always be held at a lower potential than the 5 V DC rails during power-up and power-down
transition.
IMPLICATION:The onboard video device will not initialize causing the system to display video corruption or
no video on boot.

AN430TX SPECIFICATION UPDATE
11
WORKAROUND:Use a power supply that meets the recommendation in the 2.01 ATX Specification.
STATUS:This erratum will not be fixed.
5. Memory Decrease Warning Message Not Displayed
PROBLEM:During POST, the BIOS will not generate and display a memory decrease warning message on
the screen.
IMPLICATION:The user will not be warned about a decrease in the amount of memory.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0082.P07.
6. Hard Drive Not Detected on Boot if User Defined
PROBLEM:If the drive type in BIOS Setup is set to USER, the hard drive will not be detected by the
motherboard at boot.
IMPLICATION:The hard drive will not be detected by the BIOS during the boot process and will not be
available to the operating system.
WORKAROUND:None.
STATUS:This erratum will be fixed in a future BIOS revision.
7. Intel
®
EtherExpress
™
Pro/100B Fails to Initialize With Windows* 95
PROBLEM:The system BIOS allocates 48 KB of memory at location C000H:0 rather than 44 KB as
expected.
IMPLICATION:Since the EtherExpress™Pro/100B attempts to map memory starting at location CB00H:0 by
default, this results in a resource conflict with the system BIOS. Therefore, Windows* 95 will be unable to
initialize the EtherExpress Pro/100B and an exclamation mark will be displayed in Device Manager for this
device.
WORKAROUND:Manually move the EtherExpress Pro/100B memory range to D000 or higher in Windows 95
Device Manager.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0062.P06.
8. Potential Battery Drain if No AC Power Applied
PROBLEM:A potential battery drain condition caused by the AC power loss recovery circuit can cause the
battery to source approximately 500 µA current instead of the typical 3 µA drawn when the system is powered
off. This drain condition can occur if AC power is removed from the power supply and the front panel on/off
switch is depressed.
IMPLICATION:The excessive battery drain state can result in a shortened battery life. The battery will drain
completely over a period of 3 to 4 weeks if left in this state. Reapplying AC power eliminates the excessive
battery drain condition. A battery that has been completely drained will cause a CMOS checksum error to be
displayed the next time that the system is powered on.

AN430TX SPECIFICATION UPDATE
12
WORKAROUND:None.
STATUS:This erratum was fixed in PBA revision 669379-306.
9. LS-120 Drive Does Not Work as Expected in Windows* 95
PROBLEM:After restarting Windows* 95 from MS-DOS* mode, the system BIOS does not configure the
diskette parameter table correctly if an LS-120 drive is the only floppy drive in the system.
IMPLICATION:Windows 95 will report the LS-120 drive as a hard drive instead of a floppy drive and will report
a floppy drive available as Drive A. If drive A is subsequently accessed, the system will lock up. The
problem does not occur if a 1.44 MB 3-1/2” floppy drive is also present as either drive A or drive B.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0062.P06.
10. Serial Mouse Activity Does Not Wake System After APM Shutdown
PROBLEM:The system BIOS does not recognize activity from a serial mouse as an APM event.
IMPLICATION:The system will not be restored from a power-managed state until keyboard activity occurs.
WORKAROUND:The system BIOS does recognize activity from a PS/2* style mouse.
STATUS:This erratum will be fixed in a future BIOS revision.
11. Stuck or Depressed Key During POST May Cause System Hang
PROBLEM:The BIOS is unable to detect when a key on the keyboard is stuck or depressed during Power
On Self Test (POST).
IMPLICATION:If a key is stuck or depressed during POST, the system BIOS will continue to read data from
the keyboard, resulting in a system hang condition.
WORKAROUND:None.
STATUS:This erratum will be fixed in a future BIOS revision.
12. Unable to Define IDE Heads Value for Secondary IDE Hard Drive in
BIOS Setup
PROBLEM:The Secondary IDE Master/Slave Configuration Submenu in BIOS Setup does not display a field
for the number of hard disk drive heads and has no value assigned for it in manual configuration mode.
IMPLICATION:Since BIOS setup does not allow the user to define the number of hard disk heads, thus the
system BIOS cannot detect the secondary IDE hard drive.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0062.P06.

AN430TX SPECIFICATION UPDATE
13
13. System BIOS May Corrupt Audio Add-In Card EEPROM
PROBLEM:Audio add-in cards using the Yamaha OPL3-SA2 or OPL3-SA3 audio codec have the same
hardware identification number that is used by the Yamaha audio device integrated on the motherboard. This
causes the system BIOS to inadvertently write information into the audio add-in card’s serial EEPROM during
system startup, thereby corrupting the audio add-in card’s EEPROM contents.
IMPLICATION:The audio add-in card will not operate and no audio will be available.
WORKAROUND:Disable the onboard audio in BIOS Setup before installing an audio add-in card.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0062.P06.
14. Windows* 95 Will Not Boot if LS-120 Drive is Only Device on IDE
Channel
PROBLEM:An LS-120 drive will not be recognized by Windows* 95 if it is the only device on the IDE
channel.
IMPLICATION:If an LS-120 drive is the only device on an IDE channel, a black screen with a cursor blinking
in the upper left hand corner will be displayed when Windows 95 is starting to boot and the system will hang.
WORKAROUND:The LS-120 drive is recognized when connected as either the master or the slave on an IDE
channel with another device.
STATUS:This erratum will not be fixed.
15. Advanced Power Management May Suspend System During CD-
ROM Playback
PROBLEM:ATAPI devices (such as CD-ROM and DVD drives) do not reset the inactivity timer that is used
by Advanced Power Management to determine when to place the system into suspend mode.
IMPLICATION:When playback of an audio CD or a DVD file is the only system activity, the system will go into
suspend mode when the inactivity timer expires.
WORKAROUND:Temporarily disable the Low-power standby and Shut off monitor options on the Display
Properties, Screen Saver menu. This menu is available from the Windows 95 Control Panel.
STATUS:This erratum will not be fixed.
16. BIOS Does Not Correctly Size 64 MB or Larger DIMMs
PROBLEM:Because of an incorrect register setting in the memory controller, the BIOS may not correctly
identify the size of 64 MB or larger DIMMs.
IMPLICATION:Only 16 MB of the memory will be reported by the power on self-test (POST). The additional
memory will not be available to the operating system. This erratum applies only to BIOS revision
4A3NT0X0.86A.0082.P07 and later.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0088.P09.

AN430TX SPECIFICATION UPDATE
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17. System Will Not Boot with Network as First Boot Device
PROBLEM:The feature allowing the system to boot from the network is not implemented. After the attempt
to boot from a network device selected as the first boot device fails, the system BIOS does not attempt to
boot from any additional boot devices specified in the BIOS Setup program.
IMPLICATION:If Network boot is selected as the first boot device, the system will hang.
WORKAROUND:Remove Network boot from the boot sequence.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0082.P07.
18. Unattended Start Feature Does Not Require Password Before Boot
PROBLEM:The Unattended Start feature at power on allows the system to boot without any password being
entered at the keyboard, even though a user or administrator password has been set in the BIOS Setup
program.
IMPLICATION:A system that is booted without an operator in attendance could be vulnerable to unauthorized
access.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0086.P08.
19. System BIOS Does Not Display User Logo During POST
PROBLEM:The status bit that allows display of a user logo during the POST process is disabled in some
versions of the BIOS.
IMPLICATIONS:If a user logo has been defined and loaded in the user logo flash memory area, it will not be
displayed. This erratum only affects BIOS versions 4A3NT0X0.86A.0082.P07 and later.
WORKAROUND:None.
STATUS:This erratum was fixed in BIOS revision 4A3NT0X0.86A.0088.P09.
20. System Using 3-Mode Floppy Drive Cannot Read XDF Format
Diskettes
PROBLEM:The buffer area that stores floppy drive parameters does not have room to store the speed
information to allow a 3-mode floppy drive to read a diskette in the XDF format.
IMPLICATION:A system that has a 3-mode floppy drive cannot be used to install a program or operating
system, such as PC-DOS 7.0, that is distributed on XDF format diskettes.
WORKAROUND:None.
STATUS:This erratum will not be fixed.