Introduction
The processor includes an address bus powerdown capability that removes power from
the address and data signals when the FSB is not in use. This feature is always enabled
on the processor.
Enhanced Intel® SpeedStep® technology allows trade-offs to be made between
performance and power consumptions. This may lower average power consumption (in
conjunction with OS support).
1.1
Terminology
A ‘#’ symbol after a signal name refers to an active low signal, indicating a signal is in
the active state when driven to a low level. For example, when RESET# is low, a reset
has been requested. Conversely, when NMI is high, a nonmaskable interrupt has
occurred. In the case of signals where the name does not imply an active state but
describes part of a binary sequence (such as address or data), the ‘#’ symbol implies
that the signal is inverted. For example, D[3:0] = ‘HLHL’ refers to a hex ‘A’, and
D[3:0]# = ‘LHLH’ also refers to a hex ‘A’ (H= High logic level, L= Low logic level).
Front Side Bus refers to the interface between the processor and system core logic
(a.k.a. the chipset components). The FSB is a multiprocessing interface to processors,
memory, and I/O.
1.1.1
Processor Packaging Terminology
Commonly used terms are explained here for clarification:
• Intel® Pentium® 4 processor on 65 nm process in the 775-land package —
Processor in the FC-LGA6 package with a 2 MB L2 cache.
• Processor — For this document, the term processor is the generic form of the
Intel® Pentium® 4 processor 6x1 sequence on 65 nm process in the 775-land
package.
• Keep-out zone — The area on or near the processor that system design can not
utilize.
• Intel® 945G/945GZ/945P/945PL Express chipsets — Chipset that supports
DDR and DDR2 memory technology for the Pentium 4 processor.
• Processor core — Processor core die with integrated L2 cache.
• LGA775 socket — The Pentium 4 processor mates with the system board through
a surface mount, 775-land, LGA socket.
• Integrated heat spreader (IHS) —A component of the processor package used
to enhance the thermal performance of the package. Component thermal solutions
interface with the processor at the IHS surface.
• Retention mechanism (RM) — Since the LGA775 socket does not include any
mechanical features for heatsink attach, a retention mechanism is required.
Component thermal solutions should attach to the processor via a retention
mechanism that is independent of the socket.
• FSB (Front Side Bus) — The electrical interface that connects the processor to
the chipset. Also referred to as the processor system bus or the system bus. All
memory and I/O transactions as well as interrupt messages pass between the
processor and chipset over the FSB.
• Storage conditions — Refers to a non-operational state. The processor may be
installed in a platform, in a tray, or loose. Processors may be sealed in packaging or
exposed to free air. Under these conditions, processor lands should not be
connected to any supply voltages, have any I/Os biased, or receive any clocks.
Upon exposure to “free air”(i.e., unsealed packaging or a device removed from
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Datasheet
INTEL [ INTEL ]
