SET Trace Length Requirements | Intel 440GX specs

Motherboard Layout and Routing Guidelines

In the SET topology, the only termination is on the Intel® Pentium® II processor substrate. There is no termination present at the other end of the network. Due to the lack of termination, SET exhibits much more ringback than the dual terminated topology. Extra care is required in SET simulations to make sure that the ringback specs are met under the worst case signal quality conditions.

In addition, since there is only one pull-up resistor per net the rising edge response is substantially degraded when using slow corner buffers. This effect manifests itself as a degraded flight time, which results in a reduced maximum trace length that meets the 100 MHz timing requirements. This loss of design flexibility must be carefully weighed against the cost savings from removing the resistors.

Figure 2-10. Topology for Single Processor Designs With Single-End Termination (SET)

		Intel®
1	L1	440GX
1		AGPset
Slot		AGPset
Slot

2.3.5.2SET Trace Length Requirements

Intel has performed sensitivity analysis on the SET topology. The required trace lengths for operation at 100 MHz with the SET topology are based on the sensitivity analysis results, and are listed in Table 2-3. Intel’s SET simulations were performed assuming a four layer system board, so that all traces used the microstrip propagation velocity range. The slower propagation of stripline transmission line structures is not included in the recommendations of Table 2-3.

Table 2-3. SET Trace Length Requirements

Trace	Minimum Length	Maximum Length

L1	1.50”	4.00”

Figure 2-11. Solution Space for Single Processor Designs With Single-End Termination (SET)

					2.5
						SUBSTRATE
					2.0	TRACE LENGTH
						[IN]
					1.5
0.0	1.0	2.0	3.0	4.0	5.0
			L1 [in]

Intel®440GX AGPset Design Guide

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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.

Intel 440GX manual SET Trace Length Requirements

Models: 440GX