Design Checklist

•Analog inputs feed inverting op-amp stages, useful for monitoring power supply regulation.

•The LM79 is a 5V part, however SMBus requires a 3.3V interface. Level translation circuitry is required. See the reference schematics for an example circuit.

•CHASSIS_INTRU and FAN3 are pulled down and SMI_IN# is pulled up with 10K ohm resistors.

•The LM79 is connected to a programmable chip select on the PIIX4E. This assumes that the LM79 is tied to the X-Bus. See PIIX4 Datasheet for more details.

3.18.382558B LOM Checklist

•Refer to Application Note # 383, Intel 82558 LAN on Motherboard Design Guide, for recommended PHY conformance testing (i.e., IEEE testing) and additional LOM design details.

•The PWR_GOOD circuitry (shown in Ap-Note 383) should be implemented if the power supply dose not provide this signal.

•Additional logic is needed to ensure that at least 4 clock cycles occur between ALTRST# and ISOLATE# assertion.

•The distance between “Magnetics” (i.e., Cat-3 or Cat-5 wire) and RJ-45 connector should be kept to less than one inch.

•Symmetrical 100 ohm traces should be used (differential impedance) for TDP/TDN and RDP/ RDN.

•The 82558 requires decoupling on the power pins. At minimum, 3 capacitors (2 x 0.1uF and 1 x 4.7uF) should be implemented on each side.

•High speed traces between the 82558 to magnetic or magnetic to RJ45 should be routed between layers to protect from EMI.

Pull-up resistors and values are recommended for the following pins:

Pin Number

Pin Name

Resistor Value

Comment

 

 

 

 

15

ZREF

10K (5%)

Required in both A and B stepping designs

 

 

 

 

Pull-down resistors and values are recommended for the following pins:

Pin Number

Pin Name

Resistor Value

Comment

 

 

 

 

30

TEST

1K (5%)

 

 

 

 

 

153

FLD4

10K (5%)

Not required for B-stepping designs

 

 

 

 

154

FLD3

10K (5%)

Not required for B-stepping designs

 

 

 

 

171

RDP

49.9 (1%)

 

 

 

 

 

172

RDN

49.9 (1%)

 

 

 

 

 

180

VREF

220 (5%)

 

181

RBIAS10

768 (1%)

 

 

 

 

 

182

RBIAS100

634 (1%)

 

 

 

 

 

187

TDN

49.9 (1%)

 

 

 

 

 

204

AUXPWR#

220 (5%)

 

 

 

 

 

Intel®440GX AGPset Design Guide

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Intel 440GX manual 18.3 82558B LOM Checklist, Pin Number Pin Name Resistor Value Comment
Page 93 Page 95

440GX specifications

The Intel 440GX chipset was launched in 1997 as part of Intel's series of chipsets known as the 440 family, and it served as a critical component for various Pentium II and Pentium III-based motherboard architectures. Specifically designed for the second generation of Intel’s processors, the 440GX delivered enhanced performance and supported a range of important technologies that defined PC architectures of its time.

One of the main features of the Intel 440GX was its support for a 100 MHz front-side bus (FSB), which significantly improved data transfer rates between the CPU and the memory subsystem. This advancement allowed the 440GX to accommodate both the original Pentium II processors as well as the later Pentium III chips, providing compatibility and flexibility for system builders and consumers alike.

The 440GX chipset included an integrated AGP (Accelerated Graphics Port) controller, which supported AGP 2x speeds. This enabled high-performance graphics cards to be utilized effectively, delivering many enhanced graphics capabilities for gaming and multimedia applications. The AGP interface was crucial at the time as it offered a dedicated pathway for graphics data, increasing bandwidth compared to traditional PCI slots.

In terms of memory support, the 440GX could address up to 512 MB of SDRAM, allowing systems built with this chipset to run comfortably with sufficient memory for the era’s demanding applications. The memory controller was capable of supporting both single and double-sided DIMMs, which provided versatility in memory configuration for system builders.

Another notable feature of the Intel 440GX was its support for multi-processor configurations through its Dual Processors support feature. This allowed enterprise and workstation computers to leverage the performance advantages of multiple CPUs, making the chipset suitable for business and professional environments where multitasking and high-performance computing were essential.

On the connectivity front, the chipset supported up to six PCI slots, enhancing peripheral device integration and expansion capabilities. It also included integrated IDE controllers, facilitating connections for hard drives and CD-ROM devices.

Overall, the Intel 440GX chipset represented a balanced combination of performance, flexibility, and technology advancements for its time. Its introduction helped establish a foundation for subsequent advancements in PC technology and set the stage for more powerful computing systems in the years to come.
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