Are all pentium D processors dual core?

Yes all "Pentium D" chips are dual core, and specifically refer to the code names "Smithfield" (the original Pentium D series) and it's successor, "Presler" (which did not offer any architectural advantage).

Both series were simply two Netburst architecture (Pentium 4) dies on a single MCM (multi-chip module) CPU package. Compared to Core architecture CPUs, Netburst had serious drawbacks. The main problem was the heat produced at high clock frequencies, the 130W TDP had a 4Ghz ceiling that could only be negated with high end water cooling. It was pretty clear the future belonged to more efficient dual-core CPUs on a single die.

So, during the rise of the Pentium D, AMD's Athlon 64 architecture (in particular the X2 dual-core series) gained popularity among PC enthusiasts because it was a working model of efficiency with a complete redesign of the base CPU structure - more efficient decoding stages, execution units, caches, and buses all added up to more power with less clock speed. Intel did release the "extreme edition" of the Pentium D, which AMD fans called the "emergency edition" lol... those were good times man :)

So, Intel went through a complete organizational restructure, perhaps two, and got back on track to create the Core architecture - more efficient decoding stages, execution units, caches, and buses all added up to more power with less clock speed (sound familiar? lol). They were very successful and to appease the enthusiast crowd they made them highly overclockable, some easily to 60% beyond stock speeds. Very reminiscent of the venerable Celeron 300A chip based on the Pentium 2. I had one running at 450Mhz for many years, until my generic PSU decided to bite me back for purchasing it... :(

Compared to the old Pentium 4 / netburst chips, they produced the same processing power at relatively half the clock speed, and a fraction of the heat generated. You can say they did not want to be bested by AMD, they are back - and with a vengeance :)

Well hope that is not too much of a rant, it's always a good story.

cheers

The Pentium D was Intel's answer to AMD's dual core processor. The Pentium D is to single processors bolted together to form a dual core, while the core 2 dual is actually two processors on the same die, a much more efficient and performing process then the Pentium D.

All the pentium Ds are dual core, and they are basically a lower end model of the core 2s.

Yes, however the "D" does not refer to the Dual Core, it refers to Desktop PC, you can get pentium M for mobile (single core tho)

:)

I think so, but dual cores are faster, and have bigger caches if the speds are the same ( i think)