American Megatrends MAN-772 Bedienungsanleitung

Apollo IV Pentium PCI ISA Motherboard Guide MAN-772 11/21/97[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide ii © Copyright 19 85-2010 American Megatrends, Inc. All rights reserved. American Megatrends, Inc. 5555 Oakbrook Parkway, Building 200, Norcross, GA 300 93 This publication contains proprietary information which is protected by copyright. No part of this publication may be reproduced, transcribe[...]

Preface iii Preface To the OEM Thank you for purchasing the high performance American Megatrends Apollo IV PCI Pentium ISA motherboard. This product is a state of the art motherboard that includes the famous AMIBIOS. It is assumed that you have also licensed the rights to use the American Megatrends documentation for the American Megatrends Apollo [...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide iv Packing List You should have received the following: • an Apollo IV Pentium PCI ISA motherboard, • a diskette containing the DMI Wizard 95 utility, • the American Megatrends DMI Wizard 95 User’s Guide, • an optional USB cable and mounting bracket, • two serial cables, • one paral[...]

Chapter 1 Hardware Installation 1 1 Hardware Installation Overview The American Megatrends Apollo IV PCI Pentium ISA motherboard includes the following features. CPU The CPU socket on the motherboard is a 321-pin ZIF socket. A switching voltage regulator is required. You can install any of the following CPUs: CPU Manufacturer Supported CPU Speeds I[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 2 Overview, Continued Chipset The Apollo IV PCI Pentium ISA baby-AT size motherboard uses an Intel 430TX chipset, including CPU interface controller, advanced cache controller, integrated DRAM controller, synchronous ISA bus controller, PCI local bus interface, and an integrated power management [...]

Chapter 1 Hardware Installation 3 Overview, Continued CPU Thermal Monitor The Apollo IV motherboard includes a special heat sensor under the CPU that monitors the CPU temperature. This heat sensor generates an SMI (System Management Interrupt) when the CPU temperature is too hot. The SMI can be set to turn on the external cooling fan and/or lower t[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 4 Overview, Continued PC 97 Compliant The Apollo IV motherboard is fully compliant with the Microsoft PC 97 specification at both the hardware and the BIOS levels. PC 97 is a set of hardware, bus, and device design requirements specified by Microsoft that make computers easier to use. PC 97 suppo[...]

Chapter 1 Hardware Installation 5 Overview, Continued BIOS Shadowing The system BIOS is always copied from ROM to RAM for faster execution. The end user can shadow 16 KB ROM segments from C0000h – DCFFFh. IDE The Apollo IV motherboard has two 40-pin IDE connectors onboard that support up to four IDE drives (hard disk drives, CD-ROM drives, or tap[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 6 Overview, Continued Mouse The Apollo IV motherboard includes a 5-pin berg mouse connector. USB The Apollo IV motherboard has two 4-pin USB connectors. USB allows future generations of USB-compliant peripheral devices to be automatically detected and configured through a single port. USB uses Pl[...]

Chapter 1 Hardware Installation 7 Overview, Continued DMI In a corporate environment, system manageability is an important consideration. DMI (Desktop Management Interface) is a specification for a standard method of storing and reporting system information. This motherboard supports the DMI specification on the system BIOS level. DMI detects and r[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 8 Apollo IV Dimensions Motherboard Size The Apollo IV Pentium PCI ISA motherboard is the standard baby AT size (11” by 8.6”). Motherboard Height Restrictions[...]

Chapter 1 Hardware Installation 9 Installation Steps Step Action 1 Unpack the motherboard. 2 Set Jumpers 3 Configure the CPU. Select the CPU voltage. Select the CPU speed. Install the CPU. 4 Install memory. Install system memory. 5 Install the motherboard. 6 Attach cables to connectors. Connect the power supply. Attach the keyboard cable. Connect t[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 10 Apollo IV Motherboard Layout S p ea k e r I D E L E D P W R L E D K bd L o c k R e s e t S u s p . M o d e S w it c h T u r b o L E D S u s p . L E D R e m o t e P o w e r S w i t c h[...]

Chapter 1 Hardware Installation 11 Step 1 Unpack the Motherboard Step Action 1 Inspect the cardboard carton for obvious damage. If damaged, call 770- 246 -8645. Leave the motherboard in its original packing. 2 Perform all unpacking and installation procedures on a ground-connected anti -static mat. Wear an anti -static wristband grounded at the sam[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 12 Step 2 Set Jumpers Set all jumpers and install the CPU before placing the motherboard in the chassis. Set jumpers by placing a shunt (shorting bridge) on the designated pins of the jumper. A shunt and jumpers are shown below: S hu n t 3 - p i n B e r g 2 - p i n B e r g I n t h i s m a n u a l[...]

Chapter 1 Hardware Installation 13 Step 2 Set Jumpers, Continued EP1, EP2 Flash ROM Type EP1 and EP2 are 3-pin bergs that specify the type of flash ROM installed on the motherboard. The settings are: Flash ROM Type EP1 EP2 Intel 28F001 Short Pins 2-3 Short Pins 1-2 SST 29EE010 OPEN Short Pins 2-3 MXIC MX28F2000 Short Pins 2-3 Short Pins 2-3 SST 29E[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 14 Step 3 Configure CPU Important Perform the following steps to configure the motherboard before installing a CPU. External CPU Clock CLK1, CLK2, and CLK3 are 3-pin bergs that set the CPU external clock frequency. This motherboard may have any of four different clock generators: • IMI652, • [...]

Chapter 1 Hardware Installation 15 Step 3 Configure CPU, Continued ICS 9147 Clock Generator The following CLK1, CLK2, and CLK3 settings apply only if an ICS 9147 clock generator is mounted on the motherboard. External (CPUCLK) CLK1 CLK2 FREQ1 66 6 MHz Short Pins 1-2 Short Pins 2-3 Short Pins 2-3 60 MHz Short Pins 2-3 Short Pins 2-3 Short Pins 2-3 5[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 16 Step 3 Configure CPU, Continued Summary of Jumper Setting for Intel Pentium CPUs Multi Ext. IMI 652 Clock Generator OCS 9147 Clock Generator Speed plier Speed CLK1 CLK2 CLK3 CLK1 CLK2 CLK3 FREQ1 FREQ 2 FRE Q3 P55C 233 3.5x 66 200 3x 66 166 2.5x 66 P54C 200 3x 66 166 2.5x 66 150 2.5x 60 133 2x [...]

Chapter 1 Hardware Installation 17 Step 3 Configure CPU, Continued Summary of Jumper Setting for AMD K5 and K6 CPUs Mult Ext. IMI 652 Clock Generator OCS 9147 Clock Generator Speed plier Speed CLK1 CLK2 CLK3 CLK1 CLK2 CLK3 FREQ1 FREQ2 FREQ3 K6-233 233 3.5x 66 K6-200 200 3x 66 K6-166 166 2.5x 66 K5-PR200 200 2x 66 K5-PR166 166 1.75x 66 K5-PR150 150 [...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 18 Step 3 Configure CPU, Continued VR Set Pentium CPU Voltage Install Intel Pentium CPUs that adhere to either the standard or VRE voltage specifications. VR is a 10-pin berg that sets CPU voltage. VR1 is near the top of the CPU socket. Intel Pentium CPU Markings The markings on the bottom side o[...]

Chapter 1 Hardware Installation 19 Step 3 Configure CPU, Continued Set AMD CPU Voltage Install AMD K5 and K6 CPUs that adhere to either the standard or VRE voltage specifications. VR is a 10-pin berg that sets CPU voltage. VR1 is near the top of the CPU socket. AMD K5 CPU Markings The markings on the top of the AMD K5 CPUs are: AMD-K5 AMD-K5-PRxxxA[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 20 Step 3 Configure CPU, Continued Install CPU Install the CPU in the ZIF (zero insertion force) socket by performing the following steps. The CPU socket is near one edge of the motherboard. Warning Improper CPU installation can damage the CPU and the motherboard. You must follow the procedures i[...]

Chapter 1 Hardware Installation 21 Step 4 Install Memory System Memory The motherboard has four 72-pin SIMM – Single Inline Memory Module) sockets and two 168-pin DIMM sockets. Memory must be populated one bank at a time. Each bank has two sockets. Each bank must be populated with the same type of SIMM. If a 16 MB SIMM is installed in the first s[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 22 Step 4 Install Memory, Continued Installing SIMMs The motherboard has four x 36 SIMM sockets. These sockets can be filled with either 1 MB x 36, 4 MB x 36, 8 MB x 36, or 16 MB x 36 SIMMs. Place the motherboard on an anti-static mat. With the component side of the SIMM facing you, firmly push t[...]

Chapter 1 Hardware Installation 23 Step 5 Install the Motherboard The motherboard mounting hole pattern is the same as the mounting hole pattern on the standard baby AT motherboard. Standoffs and mounting screws are not supplied with the motherboard. The chassis manufacturer should supply these parts. Step Action 1 Place the chassis on an anti -sta[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 24 Step 5 Install Motherboard, Continued[...]

Chapter 1 Hardware Installation 25 Step 6 Attach Cables Connectors The Apollo IV motherboard includes many connectors. Connection instructions, illustrations of connectors, and pinouts are: Connector Power supply connector Keyboard connector Mouse connector CPU Fan Chassis Fan Infrared Remote Power connector USB connectors Speaker IDE LED Remote Po[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 26 Step 6 Attach Cables, Continued Connect Power Supply The power supply should match the physical configuration of the chassis. Make sure that the power switch is Off before assembly. Before attaching all components, make sure that the proper voltage has been selected. Power supplies often can r[...]

Chapter 1 Hardware Installation 27 Step 6 Attach Cables, Continued Connector Keys The keys on the connector must be cut to fit on some power supplies, as shown below. Power Connector Pinout Pin Description 1 Power Good (Orange wire) (Not used) 2 VCC (Red wire) 3 +12 Volts (Yellow wire) 4 -12 Volts (Blue wire) 5 Ground (Black wire) 6 Ground (Black w[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 28 Step 6 Attach Cables, Continued Mouse Cable Attach the mouse connector cable supplied by American Megatrends to the five-pin mouse berg connector on the motherboard (labeled MS_CON ), as shown below. Attach the standard 9-pin mouse connector at the other end of the mouse cable to the mouse con[...]

Chapter 1 Hardware Installation 29 Step 6 Attach Cables, Continued When connecting chassis connectors to the motherboard, make sure to connect the correct connector end. Most connector wires are color-coded. Match the color of the wires leaving the switch or LED to the same pin on the connector end. There may be more than one connector with the sam[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 30 Step 6 Attach Cables, Continued Block Connector The Apollo IV motherboard has a 22-pin header that is used to connect the following offboard connectors. The header is on the corner of the motherboard near the CPU socket. P i n s 12 13 1 4 15 1 6 17 18 1 9 20 21 1 2 3 4 5 6 7 8 9 10 11 P i n s [...]

Chapter 1 Hardware Installation 31 Step 7 Connect Onboard I/O Onboard I/O The Apollo IV motherboard has: • two serial ports (COM1 and COM2), • a parallel port (LPT), • an IDE controller on the PCI bus. The primary IDE connector is IDE1. The secondary connector is IDE2. • a floppy controller (FDD). The serial and parallel port connectors are[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 32 Step 7 Connect Onboard I/O, Continued Parallel Port PRINTER is a 26-pin connector for a parallel port. The LPT pinout is shown below. Connect the 26-pin to DB25 cable provided with the motherboard to PRINTER. All parallel port settings can be configured through Peripheral Setup in WINBIOS Setu[...]

Chapter 1 Hardware Installation 33 Step 8 Attach Floppy Drive FLOPPY FLOPPY is a 34-pin dual-inline berg. Connect the cable from the floppy drive to FLOPPY, as shown below. The onboard floppy controller cannot be used if a hard disk card with a floppy controller is installed. Choose Standard Setup and Peripheral Setup to configure the floppy contro[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 34 Step 8 Attach Floppy Drive, Continued Floppy Connector Pinout Pin Use Pin Use 1 GND 2 DENSE1 3 GND 4 N/C 5 GND 6 DRATE0 7 GND 8 -INDEX 9 GND 10 -MOTOR0 11 GND 12 -FDSEL1 13 GND 14 -FDSEL0 15 GND 16 -MOTOR1 17 GND 18 DIR 19 GND 20 - 21 GND 22 -WDATA 23 GND 24 -WGATE 25 GND 26 -TRK0 27 GND 28 -W[...]

Chapter 1 Hardware Installation 35 Step 9 Attach IDE Drive IDE Drives Attach the IDE drives in the following manner. Choose Peripheral Setup in WINBIOS Setup to enable the onboard IDE controller. Cont’d[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 36 Step 9 Attach IDE Drive, Continued Attach IDE Cable The primary IDE (Integrated Drive Electronics) hard disk drive connector is marked PRIMARY. Both the primary master and the primary slave IDE drives must be connected by cable to PRIMARY, as shown below. PRIMARY is a 40-pin dual-inline berg t[...]

Chapter 1 Hardware Installation 37 Step 9 Attach IDE Drive, Continued PRIMARY Pinout The PRIMARY IDE pinout is: Pin Use Pin Use 1 -RESET 2 GND 3 DATA7 4 DATA8 5 DATA6 6 DATA9 7 DATA5 8 DATA10 9 DATA4 10 DATA11 11 DATA3 12 DATA12 13 DATA2 14 DATA13 15 DATA1 16 DATA14 17 DATA0 18 DATA15 19 GND 20 KEY (N/C) 21 N/C 22 GND 23 -IOW 24 GND 25 -IOR 26 GND [...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 38 Step 9 Attach IDE Drive, Continued SECONDARY IDE Pinout The SECONDARY pinout is: Pin Use Pin Use 1 -RESET 2 GND 3 DATA7 4 DATA8 5 DATA6 6 DATA9 7 DATA5 8 DATA10 9 DATA4 10 DATA11 11 DATA3 12 DATA12 13 DATA2 14 DATA13 15 DATA1 16 DATA14 17 DATA0 18 DATA15 19 GND 20 KEY (N/C) 21 N/C 22 GND 23 -I[...]

Chapter 1 Hardware Installation 39 Step 10 Test and Configure Review the following points before powering up: • make sure that all adapter cards are seated properly, • make sure all connectors are properly installed, • make sure the CPU is seated properly, • make sure there are no screws or other foreign material on the motherboard, • plu[...]

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Chapter 2 WINBIOS Setup 41 2 WINBIOS ® Setup In ISA and EISA computers, the system parameters (such as amount of memory, type of disk drives and video displays, and many other elements) are stored in CMOS RAM. Unlike the DRAM (dynamic random access memory) that is used for standard system memory, CMOS RAM requires very little power. When the compu[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 42 Using a Mouse with WINBIOS Setup WINBIOS Setup has a built-in mouse driver and can be accessed by either a serial mouse or PS/2-style mouse. WINBIOS Setup supports Microsoft- Compatible serial mice and all PS/2-type mice. The mouse click functions are: single click to change or select both glo[...]

Chapter 2 WINBIOS Setup 43 WINBIOS Setup Menu The WINBIOS Setup main menu is organized into four sections. Each of these sections corresponds to a section in this chapter. Each section contains several icons. Clicking on each icon activates a specific AMIBIOS function. The WINBIOS Setup main windows and related functions are described on the next s[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 44 Section 1 Setup Standard Setup Standard Setup options are displayed by choosing the Standard icon from the WINBIOS Setup main menu. All Standard Setup options are described in this section. Date/Time Select the S tandard option. Select the Date and Time icon. The current values for each catego[...]

Chapter 2 WINBIOS Setup 45 Standard Setup, Continued Entering Drive Parameters You can also enter the hard disk drive parameters. The drive parameters are: Parameter Description Type The number for a drive with certain identification parameters. Cylinders The number of cylinders in the disk drive. Heads The number of heads. Write Precompensation Th[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 46 Standard Setup, Continued Hard Disk Drive Types Type Cylinders Heads Write Precompensation Landing Zone Sectors Capacity 1 306 4 128 305 17 10 MB 2 615 4 300 615 17 20 MB 3 615 6 300 615 17 31 MB 4 940 8 512 940 17 62 MB 5 940 6 512 940 17 47 MB 6 615 4 65535 615 17 20 MB 7 462 8 256 511 17 31[...]

Chapter 2 WINBIOS Setup 47 Advanced Setup Advanced Setup options are displayed by choosing the Advanced icon from the WINBIOS Setup main menu. All Advanced Setup options are described in this section. System Keyboard This option does not specify if a keyboard is attached to the computer. Rather, it specifies if error messages are displayed if a key[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 48 Advanced Setup, Continued Display Add-On ROM Messages Set this option to Yes to display any additional screen messages from an option ROM. This option can only be selected if the Display BIOS POST Message option is set to No. The settings are: Setting Description Yes Display messages from an o[...]

Chapter 2 WINBIOS Setup 49 Advanced Setup, Continued Floppy Drive Swap Set this option to Enabled to permit drives A: and B: to be swapped. The settings are Enabled or Disabled . The Optimal and Fail-Safe default settings are Disabled. Floppy Access Control This option specifies the read/write access that is set when booting from a floppy drive. Th[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 50 Advanced Setup, Continued 1 st Boot Device This option sets the type of device for the first boot drives that the AMIBIOS attempts to boot from after AMIBIOS POST completes. The settings are Disabled, Network, Floppy, ARMD-FDD, ARMD-HDD, ATAPI, SCSI, CDROM, 1 st IDE-HDD, 2nd IDE-HDD, 3 rd IDE [...]

Chapter 2 WINBIOS Setup 51 Advanced Setup, Continued External Cache Set this option to Enabled to enable L2 secondary (external) cache memory. The settings are Enabled or Disabled. The Optimal default setting is Enabled. The Fail-Safe default setting is Disabled. Caching Controller Set this option to Yes if a cache controller is installed in the co[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 52 Chipset Setup The AMIBIOS Setup options described in this section are selected by choosing the Chipset Setup icon from the Setup section on the WINBIOS Setup main menu. USB Function Set this option to Enabled to enable the system BIOS USB (Universal Serial Bus) functions. The settings are Enab[...]

Chapter 2 WINBIOS Setup 53 Power Management Setup The AMIBIOS Setup options described in this section are selected by choosing the Power Management Setup icon from the Setup section on the AMIBIOS Setup main menu. Power Management/APM Set this option to Enabled to enable the Intel Triton 2 power management features and APM (Advanced Power Managemen[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 54 Power Management Setup, Continued Slow Clock Ratio This option specifies the speed at which the system clock runs in power saving states. The settings are expressed as a ratio between the normal CPU clock speed and the CPU clock speed when the computer is in the power- conserving state. The se[...]

Chapter 2 WINBIOS Setup 55 PCI/PnP Setup Choose the PCI/PnP Setup icon from the WINBIOS Setup screen to display the PCI and Plug and Play Setup options, described below. Plug and Play-Aware OS Set this option to Yes if the operating system in this computer is aware of and follows the Plug and Play specification. Windows 95 is PnP- aware. The settin[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 56 PCI/ PnP Setup, Continued IRQ3 IRQ4 IRQ5 IRQ7 IRQ9 IRQ10 IRQ11 IRQ12 IRQ14 IRQ15 These options specify the bus that the specified IRQ line is used on. These options allow you to reserve IRQs for legacy ISA adapter cards. These options determine if AMIBIOS should remove an IRQ from the pool of [...]

Chapter 2 WINBIOS Setup 57 Peripheral Setup Choose the Peripheral Setup icon from the WINBIOS Setup screen to display the Peripheral Setup options, described below. Onboard Floppy Controller Set this option to Enabled to enable the floppy drive controller on the motherboard. The settings are Enabled or Disabled. The Optimal and Fail-Safe default se[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 58 Peripheral Setup, Continued Onboard Serial Port1 Address This option specifies the base I/O port address of serial port 1. The settings are Auto (AMIBIOS automatically determines the correct base I/O port address), Disabled, 3F8h, or 3E8h. The Optimal default setting is 3F8h. The Fail-Safe def[...]

Chapter 2 WINBIOS Setup 59 Peripheral Setup, Continued Onboard Parallel Port Address This option specifies the base I/O port address of the parallel port on the motherboard. The settings are Disabled, 378h, or 278h. The Optimal default setting is 378h. The Fail-Safe default setting is Disabled. Onboard Parallel Port Mode This option specifies the p[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 60 Section 2 Security Three icons appear in this part of the WINBIOS Setup screen: • Supervisor (Password ), • User (Password ), and • Anti-Virus. Two Levels of Passwords Both the Supervisor and the User icons configure password support. If you use both, the Supervisor password must be set [...]

Chapter 2 WINBIOS Setup 61 Setting a Password The password check option is enabled in Advanced Setup (see the Advanced Setup section ) by choosing either Always (the password prompt appears every time the system is powered on) or Setup (the password prompt appears only when WINBIOS is run). The password is encrypted and stored in NVRAM. As shown on[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 62 Anti-Virus When this icon is selected from the Security section of the WINBIOS Setup main menu, AMIBIOS issues a warning when any program (or virus) issues a Disk Format command or attempts to write to the boot sector of the hard disk drive. The settings are Enabled or Disabled. If enabled, th[...]

Chapter 2 WINBIOS Setup 63 Section 3 Utility The following icons appear in this section of the WINBIOS Setup main screen: Detect IDE Choose this option to let AMIBIOS automatically detect and configure the parameters for an IDE hard disk drive. Language If this feature is enabled, you can select WINBIOS Setup messages in different languages.[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 64 Section 4 Default The icons in this section permit you to select a group of settings for all WINBIOS Setup options. Not only can you use these icons to quickly set system configuration parameters, you can choose a group of settings that have a better chance of working when the system is having[...]

Chapter 2 WINBIOS Setup 65 3 Programming the Flash ROM All versions of the Apollo IV motherboard use Flash EPROM to store the system BIOS. The advantage of Flash EPROM is the EPROM chip does not have to be replaced to update the BIOS. The end user can actually reprogram the BIOS, using a ROM file supplied by American Megatrends. Programming the Fla[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 66 Programming the Flash ROM, Continued S772P.ROM S772P.ROM resides on a floppy disk and contains the updated main BIOS code. American Megatrends will provide this file when the AMIBIOS for the Apollo IV ISA motherboard must be updated. S772P.ROM must be present in the root directory of the flopp[...]

Chapter 2 WINBIOS Setup 67 Programming the Flash ROM, Continued Beep Codes The bootblock code produces a series of beeps during Flash ROM programming to: • signify completion of a step (as shown on the previous screen), or to • signal an error. Error beeps are arranged in a coded sequence and have different meanings depending on when they occur[...]

Apollo IV PCI Pentium ISA Motherboard User’s Guide 68 Bootblock Code Checkpoint Codes Code Description E0h Verify the bootblock BIOS checksum. Disable the internal cache, DMA, and interrupt controllers. Initialize the system timer. Start memory refresh. E1h Initialize the chipset registers. Set the BIOS size to 128K. Make the 512 KB base memory a[...]