Processor Types and Specifications - Upgrading and Repairing PCs - page 103

2005. Although these processors used the code name Smithfield before their introductions, they are
based on the Pentium 4 Prescott core. In fact, to bring dual-core processors to market as quickly as
possible, Intel used two Prescott cores in each Pentium D or Pentium Extreme Edition processor.
Each core communicates with the other via th MCH (North Bridge) chip on the motherboard (see
Figure 3.33 ).
Figure 3.33. The Pentium D and Pentium Extreme Edition's processor cores communicate with
each other via the chipset's MCH (North Bridge) chip.
For this reason, you cannot use Intel 915 and 925 chipsets and some third-party chipsets made for the
Pentium 4 with the Pentium D or Pentium Extreme Edition. Intel's 945 series, 955X, and 975X
desktop chipsets, and the E7230 workstation chipset, are the first Intel chipsets to support these
processors. The nForce 4 series from NVIDIA also works with these processors.
See the Chapter 4 sections, “ Intel 945 Express Family ,” p. 203 and “ Intel 955X and 975X
Family ,” p. 204 , for more information on these chipsets.
Following are the major features of the Pentium D:
• Clock speeds of 2.66GHz-3.6GHz
• 533MHz or 800MHz processor bus
• EM64T 64-bit extensions
• Execute Disable Bit support
• 65- or 90-nanometer manufacturing process
• 2MB/4MB L2 cache (1MB/2MB per core)
• Socket T (LGA775)
The 830, 840, and 9xx models also include Enhanced Intel Speed Step Technology, which results in