1. Manuals
  2. Brands
  3. Gemlight Manuals
  4. Motherboard
  5. GMB-486UN
  6. User manual

Gemlight GMB-486UN User Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
GMB-486UN
80486 Mainboard
User's Guide
Version 3.00

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the GMB-486UN and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Summary of Contents for Gemlight GMB-486UN

  • Page 1 GMB-486UN 80486 Mainboard User's Guide Version 3.00...
  • Page 2 ABOUT THIS GUIDE This guide contains instructions for configuring and installing the GMB-486UN mainboard. • Chapter 1, Introduction, acquaints user with the special features of the GMB- 486UN mainboard. • Chapter 2, Hardware Configuration, gives information on configuring memory and setting the mainboard's jumpers. Brief sections on installing memory are also included.
  • Page 3 UNPACKING THE MAINBOARD The GMB-486UN Mainboard comes packed in a sturdy cardboard shipping carton. The carton contains: • The GMB-486UN Mainboard • This User's Guide Note: Do not remove the mainboard from its original packing until ready to install. The GMB-486UN mainboard is easily damaged by static electricity. Observe the following precautions while unpacking and installing the mainboard.

  • Page 4: Table Of Contents

    CONTENTS CHAPTER 1 INTRODUCTION KEY FEATURES MAINBOARD COMPONENTS CHAPTER 2 HARDWARE CONFIGURATION JUMPER AND MEMORY BANK LOCATIONS JP3, JP7, JP9, JP13 - CPU JUMPER SETTING CACHE CONFIGURATION 2.3.1 UPGRADING CACHE 2.3.2 CACHE SIZE AND MEMORY LOCATIONS 2.3.3 CACHE CHIP SOCKETS AND JUMPER LOCATIONS 2.3.4 JP22, JP23, JP25-30 - CACHE JUMPER...
  • Page 5 3.5.7 JP1-EXTERNAL BATTERY 3.5.8 J1-KEYBOARD CONNECTOR SYSTEM ASSEMBLY OVERVIEW CHAPTER 4 AMI BIOS SETUP STANDARD CMOS SETUP ADVANCED CMOS SETUP ADVANCED CHIPSET SETUP AUTO CONFIGURATION WITH BIOS DEFAULTS AUTO CONFIGURATION WITH POWER-ON DEFAULTS CHANGE PASSWORD HARD DISK UTILITY CHAPTER 5 HARD DISK TYPES CHAPTER 6 ERROR CODES...

  • Page 6: Chapter 1 Introduction

    CHAPTER 1 INTRODUCTION The GMB-486UN mainboard is a 2/3 body AT size high-performance mainboard that provides with the basic elements on which to build an advanced computer. This mainboard is fully IBM AT compatible, but has the added enhancement of a powerful 32-bit microprocessor.

  • Page 7: Mainboard Components

    • User Defined Password to inhibit illegal access. MAINBOARD COMPONENTS This section gives a brief description of key components on the mainboard. Refer to Fig 1 for component locations. Fig 1 Key Components of the GMB-486UN Mainboard                    !"...

  • Page 8: Chapter 2 Hardware Configuration

    CHAPTER 2 HARDWARE CONFIGURATION This chapter describes how to set the mainboard jumpers for cache memory and display type, and how to install memory modules. Before beginning the configuration, user should take the following precautions: • Turn off the power supply, and unplug the power cord before begin. •...

  • Page 9: Jp3, Jp7, Jp9, Jp13 - Cpu Jumper Setting

    For 486DX2-50 CPU, 25MHz oscillator is used instead. For 486DX2-66 CPU, 33MHz oscillator is used instead. CACHE CONFIGURATION The special feature of the GMB-486UN mainboard is a built-in direct-mapped cache controller with optional write-back or write-through operation which supports 32KB, 64KB, 128KB, or 256KB cache memory.

  • Page 10: Upgrading Cache

    Hardware Configuration 2.3.1 UPGRADING CACHE The GMB-486UN mainboard is available with an optional 32KB, 64KB, 128KB, or 256KB cache memory on-board. User can upgrade cache memory by installing additional SRAM (Static Random Access Memory) chips in sockets U36-U39 and U42-U45.

  • Page 11: Cache Chip Sockets And Jumper Locations

    Chapter 2 2.3.3 CACHE CHIP SOCKETS AND JUMPER LOCATIONS Fig 3 Cache Jumper and Socket Locations 2.3.4 JP22, JP23, JP25-30 - CACHE JUMPER SETTING Cache memory is configured using jumpers, JP22, JP23, and JP25 - JP30. JP22, JP23, and JP25 - JP30 -- Cache Size Setup...
  • Page 12 Hardware Configuration...

  • Page 13: Installing Cache Chips

    Chapter 2 Table 3: Cache Jumper Setting 2.3.5 INSTALLING CACHE CHIPS Install cache chips on the mainboard as follows: - .           "     Review the section on static electricity precautions at the beginning of this manual, and make sure that power to the mainboard is off. Align the chip so that the notched corner of the chip matches the notched corner of the socket.

  • Page 14: Jp12-Display Adapter Setup

    Hardware Configuration Carefully press the chip into the socket. Fig 4 Installing a Cache Chip JP12-DISPLAY ADAPTER SETUP Set the jumper, JP12, to configure the mainboard for either a color display card or a monochrome display card. Short the jumper for a color display adapter. Open the jumper for a monochrome display adapter.
  • Page 15 Chapter 2 Table 4...

  • Page 16: Jp2-Discharge Cmos Setup

    Hardware Configuration JP2-DISCHARGE CMOS SETUP The CMOS Setup can be erased by shorting the jumper JP2 as below. Refer to Fig 2 for the location of JP2. JP2 -- Discharge CMOS Setup Table 5 JP10-SOURCE OF GA20 The source of GA20 can be selected by JP10, when emulation fast gate A20 is selected, the system performance may optimize under Multi-user operation system.
  • Page 17 Chapter 2 Table 6...

  • Page 18: Memory Installation

    Hardware Configuration MEMORY INSTALLATION The GMB-486UN lets user add system memory via SIMM sockets on the mainboard. On-board memory is located in two banks: Bank 0 and Bank 1. See Fig 2. Four SIMM sockets are provided in each bank. User can install either a 256K, 1M, or 4M SIMM in each socket.

  • Page 19: Installing Simm

    & Chapter 2 2.7.1 INSTALLING SIMM Install a SIMM in a memory socket as follows: - .           -  "  -  Review the section on static electricity precautions at the beginning of this manual. Align the SIMM module so that the pin-1 marking on the module corresponds to the socket pin-1 marking.
  • Page 20 Hardware Configuration To fill a bank, repeat steps 1 through 4 until the sockets in each bank contain SIMMs. After installing memory, run BIOS Setup to indicate to the system for how much memory the user has installed.

  • Page 21: Chapter 3 Mainboard Installation

    CHAPTER 3 MAINBOARD INSTALLATION Once the GMB-486UN mainboard's hardware has been configured, the user is now ready to install the mainboard into the system chassis. This chapter describes what are needed to assemble an advanced computer system based on the GMB-486UN mainboard.

  • Page 22: Installing The Mainboard

    Before starting, check the location of the mounting holes in the case and on the mainboard. - .           "    Install the GMB-486UN mainboard as follows: Review the section on static electricity precautions at the beginning of this manual. Place the case on an anti-static mat and remove the cover. Remove the nylon stand-offs and screws for mounting the mainboard.

  • Page 23: Connection Locations

    Chapter 3 CONNECTION LOCATIONS Fig 6 Connector Locations CONNECTORS 3.5.1 J2/J3-POWER SUPPLY CONNECTOR The power supply connector has two six-pin male header connectors. Plug the dual connectors from the power directly onto the board connector. Description Description Power Good Ground +5V DC Ground +12V DC...

  • Page 24: Jp18-Keylock & Power Led Connector

    Mainboard Installation 3.5.2 JP18-KEYLOCK & POWER LED CONNECTOR JP18 is a keylock connector that enables and disables the keyboard and the Power-LED on the case. Description LED power Not Used Ground Keyboard Inhibiter Ground Table 9 3.5.3 JP15-TURBO SWITCH CONNECTOR JP15 connects to Turbo switch, which is used to select the mainboard's clock speed.

  • Page 25: Jp17-Speaker Connector

    Reset Open Not Reset Table 13 3.5.7 JP1-EXTERNAL BATTERY The GMB-486UN mainboard has a battery on-board; however, user can also attach an external battery to connector JP1. Using an external battery helps to conserve the on-board battery. Description VDD (6V)

  • Page 26: J1-Keyboard Connector

    Mainboard Installation 3.5.8 J1-KEYBOARD CONNECTOR A standard five-pin female DIM keyboard connector is located at the rear of the keyboard. Plug the jack on the keyboard cable into this connector. Description Keyboard Clock Keyboard Data Spare Ground +5V DC Table 15 SYSTEM ASSEMBLY OVERVIEW After installing and connecting the mainboard, assemble components in the following order:...

  • Page 27: Chapter 4 Ami Bios Setup

    CHAPTER 4 AMI BIOS SETUP The setup program provided with the mainboard is the AMI BIOS from American Megatrends Inc. Enter the AMI Setup program's Main Menu as follows: Turn on or reboot the system. After a series of diagnostic checks, the following message appears: "Hit <DEL>...
  • Page 28 BIOS Setup BIOS SETUP PROGRAM - STANDARD CMOS SETUP (C)1990 American Megatrends Inc., All Rights Reserved Date (mn/date/year): Thu, Jan 31 1991 Base memory : 640 KB Time (hour/min/sec): 15 : 23 : 15 Ext. memory : 3072 KB Daylight saving : Disabled Hard disk C: type : Not Installed...

  • Page 29: Advanced Cmos Setup

    Chapter 4 ADVANCED CMOS SETUP Run the Advanced CMOS Setup as follows. Choose "ADVANCED CMOS SETUP" from the Main Menu and a screen with a list of items appears. BIOS SETUP PROGRAM - ADVANCED CMOS SETUP (C)1990 American Megatrends Inc., All Rights Reserved Typematic Rate Programming : Enabled Turbo Switch Function : Enabled...

  • Page 30: Advanced Chipset Setup

    BIOS Setup Use the arrow keys to move between items and to select values. Modify the selected fields by using the PgUp/PgDn keys. explanation of the <F> keys follows: <F1>: "Help" gives options available for each item. <F2/F3>: Change color. <F5>: Get the old values.
  • Page 31 Non-Cacheable Block-1 Size : 0 KB Non-Cacheable Block-1 Base : 0000000H Cyrix A20M Pin : Disabled  ESC:Exit :Sel (Ctrl)Pu/Pd:Modify F1:Help F2/F3:Color F5:Old Values F6:BIOS Setup Defaults F7:Power-On Defaults Fig 9A Default Advanced Chipset Setup Screen for GMB-486UN 25MHz (486SX-25/486DX-50)
  • Page 32 Non-Cacheable Block-1 Size : 0 KB Non-Cacheable Block-1 Base : 0000000H Cyrix A20M Pin : Disabled  ESC:Exit :Sel (Ctrl)Pu/Pd:Modify F1:Help F2/F3:Color F5:Old Values F6:BIOS Setup Defaults F7:Power-On Defaults Fig 9B Default Advanced Chipset Setup Screen for GMB-486UN 33MHz (486DX-33/486DX2-66)
  • Page 33 ESC:Exit :Sel (Ctrl)Pu/Pd:Modify F1:Help F2/F3:Color F5:Old Values F6:BIOS Setup Defaults F7:Power-On Defaults Fig 9C Default Advanced Chipset Setup Screen for GMB-486UN 50MHz (486DX-50) Use the arrow keys to move between items select values. Modify selected fields using the PgUp/PgDn keys. An explanation of the <F> keys are shown on pg22 of this manual.

  • Page 34: Auto Configuration With Bios Defaults

    BIOS Setup AUTO CONFIGURATION WITH BIOS DEFAULTS This Main Menu item loads the default system values. If the CMOS is corrupted the defaults will load automatically. Choose this item and the following message appears: "Load BIOS Setup Default Values from ROM Table (Y/N)? N" To use the BIOS defaults, change the prompt to "Y"...

  • Page 35: Change Password

    Chapter 4 CHANGE PASSWORD The Main Menu item lets user to configure the system so that a password is required every time the system boots or an attempt is made to enter the Setup program. The password cannot be longer than 6 ASCII characters. A default password is stored in the ROM in case the CMOS is corrupted.
  • Page 36 BIOS Setup • Auto Interleave - determines optimum interleave factor before formatting the hard disk. • Media Analysis - analyzes each track of the hard drive. Marks unusable tracks as "bad" to prevent future data storage on those tracks. Error messages specific to the Hard Disk Utility options may appear during initialization or operation.

  • Page 37: Chapter 5 Hard Disk Types

    CHAPTER 5 HARD DISK TYPES The AMI BIOS supports the following hard disk types. Type Cyln Head WPrec LZone Sect Cap (MB) 10MB 20MB 31MB 62MB 47MB 65535 20MB 31MB 65535 30MB 65535 112MB 65535 20MB 65535 35MB 65535 50MB 20MB 65535 43MB...
  • Page 38 Type Cyln Head WPrec LZone Sect Cap (MB) 44MB 65535 69MB 41MB 65535 68MB 53MB 1024 65535 1024 94MB 1024 65535 1024 128MB 1024 1024 1024 43MB 10MB 1024 65535 1024 77MB 1024 1024 68MB 41MB 25MB 57MB 41MB 41MB 41MB 48MB 65535...

  • Page 39: Chapter 6 Error Codes

    CHAPTER 6 ERROR CODES Every time when power on the system, the POST (Power On Self Test) diagnostic routines will check to make sure the system is running properly. During boot-up, the POST communicate errors to the user as either a series of beeps, or as messages on the display screen.

  • Page 40: Error Messages

    Error Codes ERROR MESSAGES Non-fatal Error Messages usually appear on the screen as follows: ERROR Message Line 1 ERROR Message Line 2 Press <F1> to RESUME After user note the Error Message, then press the <F1> key to allow the system to proceed with boot-up.

  • Page 41: Hard Disk Utility Error Messages

    Chapter 6 Message Action On Board Parity Error Use memory diagnostic software, such as AMIDIAG, to find and correct memory problems. Off Board Parity Error Use memory diagnostic software, such as AMIDIAG, to find and correct memory problems. Parity Error ???? Use memory diagnostic software, such as AMIDIAG, to find and correct memory problems.

Table of Contents