Intel® 460GX Chipset Software Developer’s Manual 1-3
Introduction
1.2 Product Features
1.3 Itanium™ Processor System Bus Support
• Full support for the Itanium processor system bus.
— 64-bit data bus.
— 266 MHz data bus frequency.
— Cache line size of 64 bytes.
— Supports SAPIC interrupt protocol.
• Full support for 4-way multiprocessing.
• Parity protection on address and control signals, ECC protection on the data signals.
• GTL+ bus driver technology.
• High performance hardware based on IA-64
architecture
—4.2 GB/s memory bandwidth can
simultaneously support both the full system
bus and the full I/O bus bandwidths
—Architectural support for 64 MB to 64 GB of
SDRAM
—Support for up to four bridge chips that
interface to the 82461GX (SAC) through
four Expander channels, each 30 bits wide
and providing 533 MB/s peak bandwidth
—AGP 4X compatible, via the 82465GX
(GXB) and two Expander channels running
at 266 MHz totaling 1 GB/s peak bandwidth
—Support for two 64-bit, 66-MHz PCI buses
using one 82466GX (WXB) component per
Expander channel
—Support for two independent 32-bit, 33-MHz
PCI buses or one 64-bit, 33-MHz PCI bus via
the 82467GX (PXB) per Expander channel
—Data streaming support between Expanders
and DRAM, up to 533 MB/s per Expander
channel
• Extensive RAS features for mission-critical
needs
—ECC protection on the system bus data
signals
—Memory ECC with single-bit error
correction, double and nibble error detection
—Address and data flows protected by parity
throughout chipset
—ECC bits in DRAM accessible by diagnostics
—Fault recording of multiple errors; sticky
through reset
—JTAG TAP port for debug and boundary scan
capability
—I2C slave interface for viewing and
modifying specific error and configuration
registers
—Bus, memory and I/O performance counters
—Support of ACPI/DMI functions (support is
provided in the IFB)
• High bandwidth system bus for multiprocessor
scalability
—Support of the Intel® Itanium™ processor
64-bit data bus
—Full support for 4-way multiprocessing
—266 MHz data bus frequency
—Cache line size of 64 bytes
—Enhanced defer feature for out-of-order data
delivery using IDS#
—AGTL+ bus driver technology
• Features to support flexible platform
environments
—Hardware compatible with IA-32 binaries
—AGP address space up to 32 GB supported
—Support for Auto Detection of SDRAM
memory type and mixed memory sizes
allowed between rows
—Supports 16-, 64-, 128- and 256-Mbit
DRAM devices
—Full support for the PCI Configuration Space
Enable (CSE) protocol to devices on all
Expander channels
—WXB supports 3.3 volt PCI bus operation
(supports universal and 3.3 volt PCI cards)
and has an Integrated Hot-Plug Controller**
—PCI Rev. 2.2 compliant on the WXB and
PXB
—GXB supports fast writes and 1x, 2x and 4x
data rates
—1 MB or greater of firmware storage
provided by the 82802AC (FWH)
—Interrupt controller, bus-mastering IDE and
Universal Serial Bus supported by the
82468GX (IFB)
—Support of 8259A mode, APIC mode and
SAPIC mode interrupts via the
UPD55566S1-016 (PID) provided by NEC*
**Based on technology licensed from Compaq Computer Corp.