INTRODUCTION 

This manual has been designed to be useful for several purposes. If the UC4913 is already set up in functioning system, it will be helpful to review the manual to become familiar with the features of the board and where things are. This will be helpful in the unlikely event there is a problem with the system. 

For those who want to alter the board's configuration or to upgrade it, the manual will serves as a guide to both procedure and specifications. While the necessary information is included in the manual, we recommend that unless you feel confident of your ability to do the work, it would be best to have your dealer or a local service shop do it. Before making alterations to the system, check to see that doing so will not violate the system warranty. If it does, have the work done by an authorized dealer . 

IMPORTANT: 

The chipset requires correct configuration infor- mation; otherwise a malfunction may result. 

CAUTION : 

Static electricity can cause serious damage to integrated circuit chips. To avoid building up a static electric charge on your body, touch a grounded object before touching die chips and at frequent intervals as you handle die chips. If chips are handed from one person to anodier, the two should touch hands first, then pass die chips. 

1;.. 

Information presented in this publication has been carefully checked for reliability; however, no responsibility is assumed for inaccuracies. The information contained in this document is subject to change without notice. 

Contact your dealer for warranty details. 

Trademarks 
All brand and product names which appear in this manual may be trademarks or registered trademarks of their repective companies. 

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C O NfENIS 

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CHAPTER 1 INTRODUCTION 

1.1 General Specifications and Features. I-I CHAPTER 2 
MEMORY CONFIGURA TION 

2.1 SystemMemory 2-1 2.1.1 DRAM Module Insertion. 2-1 2.1.2 DRAM Module Removal. 2-2 2.2 Cache Memory Subsystem. 2-2 
CHAPTER 3 
.TUMPER SETTINGS AND CONNECTORS 

3.1 Jumper Settings 3-1 3.2 Connectors 3-4 
CHAPTER 4 
BillL T -IN BIOS SETUP PROGRAM 

4.1 SetupSummary 4-1 4.2 BIOSSetup 4-1 
4.2.1 When Should You Run Setup. 4-2 4.2.2 How to Recall the Setup Program. 4-2 4.2.3 Running the SETUP Program. 4-3 
4.3 Running the Standard CMOS Setup. 4-5 4.4 RunningtheAdvancedCMOSSetup. 4-7 4.5 Running the Advanced Chipset Setup. 4-9 4.6 UsingtheChangePasswordSetup 4-14 4.7 BIO~rrors and Messages. 4-15 ...4.7.1 Fatal Errors Through Beeps. 4-15 
4.7.2 \Non-Fatal Errors Through Beeps. 4-15 

l/rnNTF~ 

4.7.3 FatalErrorsShowninDisplay. 4-16 4.7.4 Non-Fatal Errors In Display. 4-16 4.7.5 Errors With Setup Option. 4-16 4.7.6 Errors Without Setup Option. 4-16 

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2/CONTENTS 

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]ntroduction 

Chapter 1 Introduction 

1.1 

General Specifications and Features 

The UC4913 is a cost-effective high performance mainboard based on IBM PC/AT compatible system. It uses the UM82C491 real single chip which provides high integration 486/ A T based system design. 

Processor: 

Chipset: 

System BIOS: 

K/B BIOS: 

System Memory: 

Cache Memory: 

Slots: 

80486 SX/DX PGA or 80486 SX/DX PQFP 25, 33, 50 MHz. 
80486 DX2 50,66 MHz. P23T 50,66 MHz. 
CYRIX M6 40 MHz CPU. AMD 40 MHz CPU. 

-UM82C491 real single chip. -UM82C493A TTL integration. 

AMI BIOS 64KB. 

AMI-8042KF. 

Supports 2 banks system memory up to 64 MB. 

64KB. 128KB or 256KB. 

Six 16-bit. two 8-bit ISA slots and 3 VESA slots. 

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Motherboard: 4 Layers 2/3 baby AT size. 

Connectors: 

-Power . 
-AT Keyboard. -Reset. 
-Speaker. -External battery . 

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UC491J User's Manual 

-Turbo switch. -Turbo LED -Keylock. 

Feature 
.Fully mM PC/AT compatible. 
.Support up to 64MB system memory. .Supports 64K, 128K or 256K cache- 
.Support six l6-bit, two 8-bit ISA slots. 
.Support three VESA bus masters and slaves mode. 

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Memory Configumtion 

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Chapter 2 

The UC4913 DRAM configurations are discussed, followed by DRAM module installation and removal. U sers are recommended to read through this chapter before installing or removing memory. 

2.1 System Memory 
The total size of on-board memory depends on the combinations of different types ofDRAM modules installed on the memory banks. 

Option 1 2 
.c 3 4 5 
.,.'~, 7 S 
I 9 

Bank O '!;6 KR 

256 KB 256 KB 
1 MB 1 MB 1 MB 4MB 4MB 16MB 

Bank , None 256 KB 1MB None 1 MB 4MB None 4MB None 

Memory Amount 1MB 

2MB 5MB 4MB 8MB 20MB 16MB 32MB 64MB 

2.1.1 

DRAM Module Insertion 

The SIMMs must be seated on the sockets as firmly as possible, and because of the fragility of the slot, you must be careful when inserting or removing the module. 

Align the module so the pin-l marking and corner notch of the module correspond to the SIMM socket pin 1 marking at the rear of the board. The module can fit in the socket one way only. Do not force it! 

2. Push the module against the Clip 
~ms with your thumbs until a "click" 
sound is heard; the little plastic tab appear in the latching holes on the RAM module board, and the clip rms fully grab the module board. 

UC4913 User~ Manual 

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2.1.2 

DRAM Module Removal 

If possible, use a SIMM extraction tool; otherwise use the following method 

1 

Carefully use your thumbs to bend out~rd the plastic tab ends on both sides of the slot. 

2. The RAM module board is automatically ejected off the clip arms. 

3. Take it out nfthe !:Qcket 

4. 

Repeat the steps 1 through 3 to release the other RAM modules 

2.2 Cache Memory Subsystem 
The UC4913accepts optional 64-KB, 12S-KB or 256-KB of SRAM for cache memory support. The SRAM chip should be SKxS bit or 32KxS bit. The TAG RAM is for addressing code or data from main memory to Cache memory. The table below lists all the possible cache size selections. 

Option 

64K 128K 256K 

TAG RAM IU13) 

8Kx8 8Kx8 32Kx8 

(»Is) (»Is) I2Ons) 

I DATA RAM IU14.U16.U18.U201 

8Kx812Onsl 

32KxB \ ~s; 

32KxS (2Ons\ 

I DATARAM I 
(U15.U17U19.U21) 

8Kx8 (2Ons) 

None 

32KxS ('lOns) 

2-2 

Jumper Settin&\, and Connectors 

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Chapter 3 

This chapter will assist you in setting up the UC4913 before you install it in a system case. If your UC4913 has already been installed and you do not wish to change the configuration settings, you can skip over this section. 

3.1 

Jumper Settings 

The UC4913 has several jumper switches that must be set to define a system configuration. These switches are three-pin components on the mainboard. Theyare turned off and on by placing or removing a cover cap over the pins. This is called a short or closed jumper. Alljumpers must be set to one of the possible two settings. 

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Jumper Settin&S' and COnneClO18 

The table below summarizes the function and settings of each jumper on the UC4913. 

Function 

CPU Mode Select -- 

Type of CPU used 

486PQFP 486PGA 

, 80486DX, DX2, P23T, AMD 48 6D X, M6/C 6 module 

Jumper Settings 

JP12opened JP12closed 
JP7pin 1,2& 3,4 closed 

Clock Select 

Monitor Type Select 

Cacha Memory Siza Satting 

Weitek Po_r 9CXX> VESA VGA Card 

Local Bus Speed Select 

Local Bus Write Wait Select 

80486SX, M6.AMD486SX 

25 MHz 

33 MHz 

40 MHz 

5OMHz 

Mono Color 64K 

128 K 

256K 

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Installed Non-lnstalled < =33MHz > 33MHz OWait 1 Wait 

JP7 pin 2,3 closed 
JP9 closed JP10 closed 
JP9 opened JP10 closed 
JP9 closed 
JP10 opened 
JP9 opened 
JP10 opened 
JP11 pin 1,2 closed JP11 pin 2.3 closed JP13opened 
JP15 opened 
JP16 pin 1,2 closed JP17 opened 
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! JP13 pin 2.3 closed JP15opened 
JP16 pin 2.3 closed JP17 closed 
JP13 pin 1,2 closed JP15 closed JP16pin 1,2 closed JP17 closed 
JP18 pin 2.3 closed JP18pin 1,2 closed JP2 opened JP2 closed 
JP1 opened 
"'-- JP1 closed 

UC4913 User:S-Manual 

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3.2 

Connectors 

There are several connectors located on the UC4913. They are used to connect with some peripheral devices to enhance the operating performance of the system. 

Refer to Figure 3.1 for the positions of all the connectors on the mainboard Their functions are listed below: 

Connector J3 
JP14 

- Po_r Connector 
Keyboard Connector 
J2 External Battery Connector JP4 Turbo Swtch Connector JP6 Kaylock Connector 
JP3 Turbo LED Connector JP6 Reset Connector 
J1 Speaker Connector 

Function 

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Built-in BIOS Setup Program 

Chapter 4 
Built-in BIOS Setup Program 

This chapter provides detailed instructions on h(1tN to configure your system using the Built-in BIOS Setup program and gives some technical information about your computer. If you are not very familiar with microcomputers, please read this chapter carefully before proceeding. .If you do not want to change the system's configuration, you can skip this chapter. 
Before you start to add optional devices to your system, you should fIrst learn h(1tN to set up your system and adjust its jumpers (Refer to Chapter 3 for detailed information). You may run the Setup program of the UC4913 only after all jumper setting adjustments have been completed. At this time you should record what the configuration is, and keep it for reference. 

4.1 Setup Summary 
I. Install any extra memory SIMMs. 2. Make all connections to board. 
3. Install control cards, monitor, and any peripheral devices and drivers. 4. Turn on system. 
5. At setup prompt, press the Del key. 
6. Type the password if you set the password checking option to "Setup" or "Always" in the Advanced CMOS Setup program. 
7. Choose Standard CMOS, Advanced CMOS or Advanced Chipset Setup. 8. Follow screen prompts. 

4.2 BIOS Setup 
Every AT -compatible computer has battery supported CMOS memory other- wise called "non-volatile" RAM. It stores information about your computer and peripheral device configuration. Unlike ordinary RAM, it retains the information even after you turn off your computer. 
A computer needs to kn(W certain things about itself so it can operate correctly when powered on. A special type of software called BIOS (Basic Input Output System) is contained in read-only memory (ROM) chips on the mainboard. The BIOS reads information from the CMOS memory every time you power on the computer. It then instructs the CPU and other devices to operate according to this information. If the information it retrieves is incorrect or insufficient, 

UC4913 User's Manual 

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the system may not be able to operate properly until accurate information is supplied. You do this by means of the SETUP program built in the system BIOS. 
4.2.1 When Should You Run Setup ? 
I. Although someone may have set up the system for you, you may want to adjust the system to fit your needs. 
2. Whenever you change some components in your system, (for example, if you add a hard disk or more memory), you must run Setup to record the new system configuration. If you don't do so after adding memory, the computer will prompt you to run Setup. 
3. The last and most unlikely possibility is the loss of information in the CMOS memory. You may never encounter this situation. But if you do, you can restore the information by running the Setup. 

4.2.2 How to Recall the Setup Program ? 
You can run the built-in SETUP program in several ways: I. When powering-on the system 
When you turn on the system power or press the reset button on the system case while the system is running (not every system has this button), the BIOS will first test the functionality of the system components and display a start-up message similar to the following: 
XXXX KB OK 
Hit < Del > ,If you want to run Setup 
The numeral digits will continue to count at the top left of the screen. This represents the BIOS testing the mainboard memory chips. Before the above message disappears, you can press the < Del > key to run the Setup program. 
2. To reset the system By pressing <Ctrl> <Alt> <Del> key combination when the system is up and running (assuming you are running under DOS or other environments that support this feature), the system will immedi- ately reset itself and boot up. Before booting up from a diskette or hard disk, you can also see the below start-up message : 

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3. 

When the BIOS prompts you 
In the self-test process, if the BIOS detects inconsistent or incorrect 

Built-in BIOS Setup Program 

4 

configuration information or some physical system error, it will display an error message on the screen, and prompt you to take action; for example: 

Press the < Fl > key, and continue. 

To Enter password If you set the password checking option to the "Setup" or " Always" field in the Advanced CMOS Setup program, after pressing the "Del" key to run the Setup program, the Enter password message will be displayed on the screen. Refer to section 4.6, Using the Change Password Setup. 

4.2.3 Running the SETUP Program 
When you call up the Setup program, the screen displays a "main menu" similar to the follcr.ving: 
On-screen instructions at the bottom of the screen explain how to use the program. 

STANDARD CMOS SETUP ADVANCED CMOS SETUP ADVANCED CHIPSET SETUP AUTO CONFIGURATION WITH BIOS DEFAULTS CHANGE PASSWORD AUTO DETECT HARD DISK WRITE TO CMOS AND EXIT DO NOT WRITE TO CMOS AND EXIT 

Figure 4.1 BIOS Setup Main Menu Options 

The following is a brief description of the six options of the Setup main menu 

UC491J User's Manual 

.STANDARD CMOS SETUP 
Display the standard CMOS Setup screen to check or modify general configu- ration information. The standard CMOS setup displays the date, time, floppy type, bard disk type, video type, etc. .ADVANCED CMOS SETUP 
The ADVANCED CMOS SETUP option is used to set the wrious system options for the user, including the above 1 MB memory test, etc. 
.ADVANCED CHIPSET SETUP This Setup option is for the user who wishes to program the chipset registers. The chipset registers control most of the system options in the computer, etc. 
.AUTO CONFIGURATION WITH BIOS DEFAULTS 
This option allows for automatic configuration of all the options in the Advanced CMOS Setup/Advanced Chipset Setup with the BIOS defaults. 
.CHANGE PASSWORD 
The pasbWord is required for entering the Setup program or booting your system. The user can change the current pas&WOrd stored in the CMOS by accessing this option. 
.AUTO DETECT HARD DISK 
This option allows for automatic detect the type of hard disk drive, include the number of cylinders and heads, write pre-compensation time, read/ write head 
landing zone, number of sectors per track. .WRITE TO CMOS AND EXIT 
Choose this option to save the changes you have made in the "Standard 
Setup"," Advanced Setup" and "Advanced Chipset" options, and then exit to reboot the system- 
.DO NOT WRITE TO CMOS AND EXIT 
Choose this option to abandon all previous settings and then exit to reboot the system. 
To choose an item from the Setup main menu, move the cursor to appropriate line using the Up< t > and Down < .!. > arrow keys and press < Enter > .The screen will display a warning message as below: 

4-A 

Built-in BIOS Setup Program 

AMIBIOs SETUP PROGRAM -WARNING INFORMATION ICI 1993 American Megatrends. Inc.. All Rights Reserved 

Improper Use of Setup May Cause Problems!! 00 System Hangs, Reboot System and Enter Setup by Pressing the < Del > Ke'. Do Any of the Following After Entering Setup 
(i) Alter Options to Make System Work 
I(ii) Load BIOS Setup Defaults (iii) Load Power-On Defaults 
Hit < ESC > to Stop Now, Any Other Key to Continue Figure 4.2 BIOS Setup Warning Message 4.3 Running the Standard CMOS Setup 
To check or modify the general system configuration, choose "STANDARD 
CMOS SETUP" from the Setup main menu and press <Enter> .The screen will display the foll<M'ing: 

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UC4913 User's Manual 

Oo-screen instructions in the lower left comer of the screen explain h(1tN to use the program. After making all selections, press < ESC > key and then return to the main menu program to choose another Setup program. 
.Date 
In the Date fields, you manually set the electronic calendar on the mainboard only if the values are incorrect. 
.Time 
Time fields include hour, minutes, seconds, but you can only set the value of hour and minute. Check and adjust these fields according to your clock or wrist watch. 
.Floppy Drive A and B 
In this field you may specify the capacity and format of the floppy drives installed in your system. 
.Hard Disk C: and Hard Disk D: In these fields, you specify the physical and electronic properties of the "standard" hard disk drives installed in your system. Relevant specifications include the number of cylinders and heads, write pre-compensation time, read/write head landing wne, number of sectors per track. 
The BIOS provides 46 predefined types of popular hard disk drives. You select 
the appropriate type by scrolling forward/backward using the < PgUp > and < PgDn > keys. The relevant specifications of the selected drive will be immediately displayed on the corresponding field positions. 
If for some reasons your particular drive is not one of the 46 predefined types, simply scroll down to select type 47, then use the left < +- > and right < ~ > arr(1tN keys to move to the Cyln(Cylinders), Head, WPcom(Write Pre-Com- pensation), LZone(Landing Zone), and Sec(Sectors) fields and directly key in 
the appropriate values. The Setup program will calculate the capacity of the drive based on the input cylinder, head and sector numbers and display the result on the capacity field for your reference. 
Refer to Appendix A for the table of hard disk types. .Primary Display 
In the display field, you specify the display adapter installed in your system. .Keyboard 
This setting is used to select "Installed" or "Not Installed" for the keyboard during the Power On Self Test. Normally, it should be set as "Installed". 

4-6 

Built-in BIOS Setup Program 

.Base Memory and Extended Memory 
A small section in the upper right comer of the screen displays important status information on your system, including base and extended memory amount. They are updated automatically by the Setup program according to status detected by the BIOS self-test; no manual change is allowed. 

4.4 Running the Advanced CMOS Setup 
When you choose the "RUN Adwnced CMOS Setup" option in the Setup main menu, the screen displays the following menu: 

.Above 1 MB Memory Test 
You can disable this option to pass the memory test if a lot of memory is installed in the system, or you can enable this option to test all the memory. 
.Hard Disk Type 47 RAM Area 
The purpose of this field is to specify the address of the memory area used by the system BIOS for storing extended information, such as to save the user definable drive type 47. 
You have the foll(M'ing options: 
.0:300 
To reserve the stack area at address 30h:0. 

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UC491J User's Manual 

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DOS lKB 
To reserve the top 640 KB in the DOS base memory and reduce the size of base memory by 1 KB. 

.Cyrix Coprocessor 
The awilable options are listed below: Absent Present 
.Floppy Drive Seek At Boot 
The awilable options are listed below: Disabled. Enabled. 
.Extemal Ilnternal Cache Memory 
The awilable options are listed below: Disabled. Enabled. 
.Password Checking Option 
The purpose of this field is to determine whether the password is asked for every boot (set to "Always") when entering into the Setup program (set "Setup") If you ~uld like to disable pas~rd, please refer to section 4.6. 

4-8 

Buill-in BIOS Setup Program 

4.5 Running the Advanced Chipset Setup 
To program the registers of the chipset, choose the " Advanced Chipset Setup " option from the Setup main menu and press < Enter > .The screen will display the following menu: 

AMIBIOS SETUP PROGRAM -ADVANCED CHIPSET SETUP (C11993 American MeQatrends Inc.. All Rights Reserved 
Auto-Config Function Enabled 
IMemory Remapping 
Cache Read Option 3-2-2-2 Segment Shadow RAM 
Cache Write Option. 2 W.S. Segment Shadow RAM DRAM Type FastPage : COOO-C3FF Shadow RAM ORAM Wait State(sl 2 W.S. C400-C7FF Shadow RAM 
Keyboard Clock Select CPUCLKI4 16 BIT DMA WAIT STATES AT Clock Select CPUCLKI4 8 BIT DMA WAIT STATES 10 Recovery Time 513 BCLK Hold PD Bus 1-2 T Refresh Cycle Slow 
Coprocessor Ready Delay 1 T Check ELBA# Signal in T2 
Non-Cacheable Block 1 Enable: Disabled Non-Cacheable Block-1 Size: 4MB Non-Cacheable Block-1 Base: OKB 
Non-Cacheable Block-2 Enable: Disabled Non-Cecheable Block-2 Size: 16MB Non-Cacheable Block-2 Base: OKB 
~--Esc~Exi;-i:t;s:1 (c;rll PulPd: Modify F1: Help F21F3: C 
r-.-i F5: Old Values F6: BIOS Setup Defaults F7: Power-On Defaults r I 
Figure 4.5 The Advanced Chipset Setup .Auto-Config Function 
If this function is enabled, it is no use about the under list function:(AUTO) .Cache Read Option 
.Cache Write Option .DRAM Type 
.DRAM Wait State(s) 
.Hold PD Bus for DMA/Master .Keyboard Clock Select .AT Clock Select 
.10 Recovery Time ofISA/PCB 
If disabled, user selected values for above parameters will be used. The available options are listed below: 
.Disabled .Enabled 

Enabled Enabled Disabled Enabled Enabled 1 W.S 1 W.S 

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UC4913 User's Manual 

.Cache Read Option Due to constraint for technology, speed of currently available SRAM may not 00 high enough to catch up with the speed of the CPU, which means that at every step of program execution, the CPU must wait for the SRAM to respond. This option determines the numOOr of cycle times to be inserted when CPU read data to SRAM. 
Moreover, the setting depends on the speed of the CPU and SRAM. If the 
CPU is of high speed, the timing of SRAM processing data needs an extension, except for some SRAMs that can be high enough to catch up with the speed of CPU. 
The available options are as follows: .2-1-1-1 
.3-1-1-1 .3-2-2-2 
.Cache Write Option 
The setting of Cache Write Hit Wait State makes no difference from that of 
Cache Read Hit Burst. It is important to check your speed of the CPU & SRAM OOfore you change the default value. 
The options are available as follows: 
.OWS .1 WS .2WS 

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.DRAM Type ~~~ The available options are listed below: - 
.Fast Page 
.Page Mode 
.DRAM Wait State(s) 
This option determines the number of wait states to be inserted when the CPU writes data into the local DRAM. The available options are as follows: 
.O WS .2 WS .1 WS 

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Built-in BIOS Setup Program 

.Keyboard Clock Select 
The available options are listed below: .CPUCLK/6 (50 MHz is recommended) .CPUCLK/5 
.CPUCLK/4 (33 MHz is recommended) .CPUCLK/3 (25 MHz is recommended) .CPUCLK/2 (16/20 MHz is recommended) .9.5 MHz .7.2 MHz 

.AT Clock Selection 
The AT Clock is an output clock for the 1/0 channel. This field is used to specify the 1/0 BUS clock source used by the system. The user does not need to change this setting. 
The available options are listed bel(YoN: 
.CPUCLK/8 
.CPUCLK/6 (50 MHz is recommended) .CPUCLK/5 
.CPUCLK/4 (33 MHz is recommended) .CPUCLK/3 (25 MHz is recommended) 
.CPUCLK/2 (16/20 MHz is recommended) 
.110 Recovery Time Delay 
This field is used to specify the 1/0 command recovery time except for some add-on cards which cannot work properly. It is recommended to set this option at "low" value to enhance the 1/0 performance. 
.Hold PD Bus 
The available options are listed bel(YoN: ',cc -~ ~'-~ 
1 2T ""c ?"c~ : 2~3T 
.Refresh Cycle ;;l~,i ) ,,)"? 
c"):!))C, The available options are listed bel(YoN: ;;"'~~i;\: ~~~ 3 ";0;"j ,',;.,~,t:;,: 
.Slow .Fast 
.CoProcessor Ready 
The available options are listed bel(YoN: 
.Delay IT 
.No Delay ~'~ci,jw.;f; 

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UC4913 User's Manual 

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.Check ELBA# Signal 
The available options are listed below: .in TI 
.in T2 (Default) 
.Non-Cacheable Block 11Block2 Enable 
If this function is disabled, the setting of Non-Cacheable Block-l/Block-2 Si2 and Non-Cacheable Block-lIBlock-2 Base will be invalid. .Non-Cacheable Block-1IBlock-2 Size 
For some special 1/0 cards which need to use system mernroy, you shoul reserve some memory space for use. The size of the block-l/block-2 can be a sarnll as 16KB/64KB or as large as 4MB/16MB. The address of the block l/block-2 is a mulitiple number of its size. 
The options of Non-Cacheable Block-l Size are as follows: .16 KB .512 KB 
: ~~8~B : ~~: - 
.256KB r(!'ti,"'~ The options of Non-Cacheable Block-2 Size are as follows: ~: '"0-:"' 
.64KB .2MB .. .128 KB .4MB .256 KB .8MB 
.512 KB .16 MB .1MB 
According to the above settings, you should set the proper address. .Non-Cacheable Block-1IBlock-2 Base 
This function is to set the address of Non-Cacheable Block-l/Block-2 Basc from starting. 
.Memory Remapping 
This option enables or disables the system to map the 384KB memory to address above the 1MB boundary. This function cannot be used when the system memory is bel(M' 1MB. If shadow RAMs are enabled, only 256KB memory can be remapped. 
.FIE Segment Shadow RAM 
The available options are listed bel(M': .Disabled 
.Enabled 

Built-in BIOS Setup Program 

.Cached 
.In to-4 86 
.COOOO-CJFFF Shadow RAM 
If you have a shadO'Ning of the video BIOS at C0000-C3FFF, 16K, you can enable this memory cacheable function. 
.C4000-C7FFF Shadow RAM 
If you have a shadO'Ning of the video BIOS at C4000-C7FFF, 16K, you can enable this memory cacheable function. 
.16 BIT DMA WAIT STATES 
The available options are listed belO'N. .1 W.S. (default) .2 W.S. 
.3W.S. .4W.S. 

.S SIT DMA WAIT STATES 
The available options are listed bel(M'. .1 W.S. (defuult) .2 W.S. 
.J W.S. .4 W.S. 

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4.6 Using the Change Password Setup 
To change the password, choose the "CHANGE PASSWORD" option fron the Setup main menu and press < Enter > . 
I. If the CMOS is bad or if this option has never been used, the user ii 
asked to enter new pas~rd. The screen will display the followinl message: 
I Enter NEW Password: I 
If you want to disable the pas~rd fwtction, you can press < Enter > key to return to the Main Setup menu. 

2. If the CMOS is good or if this option has been used to enter thf password, the user is asked for the password stored in the CMOS. Thf screen will display the foll(M'ing message: 
I Enter Current Password: I Enter the correct password and continue to change the password. 
3. After pressing the current password, you can change the password stored 
in the CM OS. The password can be at most 6 characters long. To change the password, please foll(M' the steps bel(M': 

I 

Re-Enter NEW Password: 

Note 

. If you want to disable the pass- word function, you can press < Enter > key in this option. The pas&WOrd prompt will not appear when the system is pow- ered on. 

Pre~~ < Enter > and reblrn to main menu 

11_1 A 

Built-in BIOS Setup Program 

4.7 BIOS Errors and Messages 
After entering setup choices, the system will reboot. The setup summary and system information will appear on screen along with messages. These may include ERROR messages concerning the system or setup. 
AMI BIOS performs various diagnostic tests at the time the system is turned on. Whenever an error is encountered during these tests, there will be either a few short ~ps or an error displayed on the monitor. If the error occurs before the display device is initialized, the system reports the error with several short beeps. 
If die error is FATAL, the system halts after reporting the FATAL error. If the 
error is NON-FATAL, the process continues after reporting the error. 

4.7. 1 Fatal Errors Through Beeps 
These errors are conveyed through a number of beeps. 

Beep Count 
1 2 4 5 6 7 9 

Meaning 

DRAM Refresh Failure 
Base 64 KB RAM Failure System Timer Failure Processor Failure 
Keyboard ~troUer-GJ\TS A20 Srror Virtual Mode Exception Error ROM-BIOS CheckSum Fajlure 

4.7.2 Non- Fatal Errors Through Beeps 
These errors are conveyed as one long beep follO'Ned by several short beeps. 

Beep Count 
3 8 

Meaning 

Conventional and Extended Memory Test Failure IDisplay Test and Vertical and Horizontal Retrace Test Failure 

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4.7.3 Fatal Errors Shown in Display 
When these errors are displayed, the screen is cleared, and the error message display is followed by a line saying SYSfEM HALTED. 
I. CMOS INOPERATIONAL: indicates failure of CMOS shutd<M'D register test. 
2. 8042 GATE-A20 ERROR: error in getting into protected mode. 3. INVALm SWITCH MEMORY FAILURE 
4. DMA ERROR: DMA controller page register test failed. 5. DMA #1 ERROR: DMA Unit I register test failed. 6. DMA #2 ERROR: DMA Unit 2 register test failed. 

4.7.4 Non- Fatal Errors In Display 
There are two types of errors in this category: 
1. One that requires you to press the Fl key and give you the option of 
nmning SETUP. 
2. One that requires you to press the Fl key and don't give you the SETUP option. 
4.7.5 Errors With Setup Option 
1. CMOS battery state low indicates failure of CM OS battery or a failure in the set and checksum tests. 
2. CMOS system options not set indicates failure of CMOS battery or a failure in the set and checksum tests. 
3. CMOS checbwn failure indicates CMOS battery 1(1oN or a failure in the set and checksum tests. 
4. CMOS display type mismatch indicates failure of display verifica- tion. 
5. CMOS memory size mismatch indicates system configuration and setup failure. 
6. CMOS time & date not set indicates system configuration verifica- tion error and setup error (in timer). 
4.7.6 Errors Without Setup Option 
1. CH-2 timer error indicates cbanneI2.1.0 timer test failure. 

Built-in BIOS Setup Program 

2. keyboard error indicates keyboard test failure. 
3. KB/Interface error indicates keyboard test failure. 
4. Display switch setting not proper indicates display ty~ verification error. 
5. Keyboard is locked Unlock it. 
6. FDD controller error indicates system configuration verification error 
in diskette setup. 
7. HDD controller failure indicates system configumtion verification error in hard disk setup. 
8. C:Drive error indicates hard disk setup error. 9. D:Drive error indicates hard disk setup error. 10. D:Drive failure indicates hard disk failure. 

Appendix A 

There are two methods to select the system processing speed. You can change the speed during operation while you are working with your application program. 

~ 

High Speed 

~ 

(Ctrl) +(Alt) +( + ) Low Speed 
(Ctrl) +(Alt) +( -) 

+ 

+ 

~ 

~ 

+ 

+ 

* 

" + " means one must press the keys simultaneously. 

~ 

9