Introduction

1.3.2.4PCI Interface

The 82443GX PCI interface is 33 MHz Revision 2.1 compliant and supports up to five external PCI bus masters in addition to the I/O bridge (PIIX4E).

1.3.2.5System Clocking

The 82443GX operates the system bus interface at 100 MHz, PCI at 33 MHz and AGP at 66/133 MHz. The 443GX clocking scheme uses an external clock synthesizer which produces reference clocks for the system bus and PCI interfaces. The 82443GX produces a single 100 MHz SDRAM clock output which is fed to a 1 to 18 clock buffer to support 1 to 4 DIMMs.

1.3.3PCI-to-ISA/IDE Xcelerator (PIIX4E)

The PCI-to-ISA/IDE Xcelerator (PIIX4E) is a multi-function PCI device implementing a PCI-to- ISA bridge function, a PCI IDE function, a Universal Serial Bus host/hub function, and an Enhanced Power Management function. As a PCI-to-ISA bridge, the PIIX4E integrates many common I/O functions found in ISA-based PC systems; a seven channel DMA Controller, two 82C59 Interrupt Controllers, an 8254 Timer/Counter, and a Real Time Clock. In addition to Compatible transfers, each DMA channel also supports Type F transfers.

The PIIX4E contains full support for both PC/PCI and Distributed DMA protocols implementing PCI based DMA. The Interrupt Controller has Edge or Level sensitive programmable inputs and fully supports the use of an external I/O Advanced Programmable Interrupt Controller (APIC) and Serial Interrupts. Chip select decoding is provided for BIOS, Real Time Clock, Keyboard Controller, second external Microcontroller, as well as 2 Programmable Chip Selects. The PIIX4E provides full Plug and Play compatibility. The PIIX4E can be configured as a Subtractive Decode bridge or as a Positive Decode bridge.

The PIIX4E supports two IDE connectors for up to four IDE devices providing an interface for IDE/EIDE hard disks and CD ROMs. Up to four IDE devices can be supported in Bus Master mode. The PIIX4E contains support for “Ultra DMA/33” synchronous DMA compatible devices.

The PIIX4E contains a Universal Serial Bus (USB) Host Controller that is Universal Host Controller Interface (UHCI) compatible. The Host Controller’s root hub has two programmable USB ports.

The PIIX4E supports Enhanced Power Management, including full Clock Control, Device Management for up to 14 devices, and Suspend and Resume logic with Power On Suspend, Suspend to RAM or Suspend to Disk. It fully supports Operating System Directed Power Management via the Advanced Configuration and Power Interface (ACPI) specification. The PIIX4E integrates both a System Management Bus (SMBus) Host and Slave interface for serial communication with other devices.

For more information on the PIIX4E, please refer to thePIIX4 datasheet.

1.3.4 Wired for Management Initiative

Wired for Management (WfM) is an Intel initiative to improve the manageability of desktop, and server systems. The goal of WfM is to reduce the Total Cost of Ownership (TCO) through improved manageability in the following four technology areas:

•Instrumentation

•Remote Service Boot

•Remote Wake-Up

•Power Management

Intel®440GX AGPset Design Guide

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Intel 440GX manual PCI-to-ISA/IDE Xcelerator PIIX4E, PCI Interface, System Clocking, Wired for Management Initiative
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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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