HP 525 5/XX, 520 5/XX manual Principal Components and Features, PCI Chipset, Host Bus

3 System Board (P/Ns D3657-63001 and D3661-63001)

Principal Components and Features

Principal Components and Features

PCI Chipset

The PCI chipset consists of four chips that interface between the three main buses (the processor’s local (PL) bus, the PCI bus, and the ISA bus):

•The PL/PCI bridge chip (SB82437FX-66) which also provides control for the PCI bus, level-2 cache memory, and main memory.

•Two data path unit chips (SB82438FX) that provide a 64-bit data path between the processor local bus and main memory modules.

•The PCI/ISA bridge chip (SB82371FB) also provides control for the IDE.

Pentium

Processor

Host Bus PCI Bus

SB82438FX

Data Path Unit

SB82438FX

Data Path Unit

Main

Memory

Level-Two

Cache

SB82437FX-66 PCI, Cache

and Memory Controller

Cache	Main
Controller
	Memory
Write	Controller
Buffer

PCI	PCI
Master	Slave

ISA Bus

SB82371FB

PCI/ISA Bridge

PCI
Master	ISA Bus
	Controller
PCI
Slave
APIC	IDE
	Controller

BIOS

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