Pentium D is a dual-core version of Pentium 4, and Pentium Extreme Edition is a Pentium D with HyperThreading technology enabled. Pentium D and Pentium Extreme Edition CPUs can be found using two different core versions: Smithfield and Presler. In this tutorial we will talk about these two core versions and we will also list all Pentium D and Pentium Extreme Edition models released to date.
Pentium D and Pentium Extreme Edition are based on Intel’s 7th generation microarchitecture, a.k.a. Netburst. I.e. besides their different name, Pentium D and Pentium Extreme Edition are internally a Pentium 4. The basic difference between Pentium D and Pentium Extreme Edition is the absence of the HyperThreading technology on Pentium D.
Do not confuse Pentium Extreme Edition with Pentium 4 Extreme Edition. The former is a dual-core processor, while the later is a single-core CPU.