Chip-Set - HP Vectra VA6 Technical Reference Manual

Chip-Set

The Intel 82440 FX chip-set comprises three chips. Two are concerned
with controlling memory accesses. These are the data bus accelerator
(DBX) chip (SB82442FX) and the combined PL/PCI bridge and memory
controller (PMC) chip (SB82441FX). The DBX chip, controlled by the PMC
chip, implements a 64-bit data path (not interleaved) between the
Processor-Local bus and main memory modules.
Processor-Local Bus
Pentium Pro
Processor
The PCI/ISA Bridge chip (otherwise known as PIIX3, or as the system I/O
chip, SIO-A) is an Intel SB82371SB. It is not only responsible for
transferring data between the PCI bus and the ISA expansion bus, but also
contains the IDE controller.
82442FX
Data Bus Accelerator (DBX)
Clocks
Host
Interface
and Misc.
DRAM
PMC
Interface
Interface
Main
Memory
DBX
Main
Interface
Memory
Controller
Clocks
and Misc.
PCI
Host
Interface
Interface
82441FX
PL/PCI Bridge (PMC)
Devices on the Processor-Local Bus
PCI Bus
82371SB
PCI/ISA Bridge
PCI
Master
PCI
Slave
APIC
BIOS
2 System Board
ISA Bus
ISA Bus
Controller
IDE
Controller
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