Processor/Memory Subsystem
3.2Intel Processors
These systems each feature an Intel processor in a FC-LGA775 package mounted with a heat sink in a zero-insertion force socket. The mounting socket allows the processor to be easily changed for upgrading.
3.2.1 Intel Processor Overview
The models covered in this guide support Intel Celeron, Pentium, and Core 2 processors, including the latest Intel Core 2 Duo, and Core 2 Quad processors.
Key features of supported Intel processors include:
■Dual- or quad-core architecture—Provides full parallel processing.
■Hyper-Threading Technology—Featured in some Intel Pentium and Core Processors, the main processing loop has twice the depth (20 stages) of earlier processors allowing for increased processing frequencies.
■Execution Trace Cache— A new feature supporting the branch prediction mechanism, the trace cache stores translated sequences of branching micro-operations ( ops) and is checked when suspected re-occurring branches are detected in the main processing loop. This feature allows instruction decoding to be removed from the main processing loop.
■Rapid Execution Engine—Arithmetic Logic Units (ALUs) run at twice (2x) processing frequency for higher throughput and reduced latency.
■Up to 8-MB of L2 cache—Using a 32-byte-wide interface at processing speed, the large L2 cache provides a substantial increase.
■Advanced dynamic execution—Using a larger (4K) branch target buffer and improved prediction algorithm, branch mis-predictions are significantly reduced
■Additional Streaming SIMD extensions (SSE2 andSSE3)—In addition to the SSE support provided by previous Pentium processors, the Pentium 4 processor includes an additional
144 MMX instructions, further enhancing:
❏Streaming video/audio processing
❏Photo/video editing
❏Speech recognition
❏3D processing
❏Encryption processing
■Quad-pumped Front Side Bus (FSB)—The FSB uses a 200-MHz clock for qualifying the buses' control signals. However, address information is transferred using a 2x strobe while data is transferred with a 4x strobe, providing a maximum data transfer rate that is four times that of earlier processors.
The Intel processor increases processing speed by using higher clock speeds with hyper-pipelined technology, therefore handling significantly more instructions at a time. The Arithmetic Logic Units (ALUs) of all processors listed above run at twice the core speed.
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