The these both processors have only 2 cores, the major difference is the bandwidth.. i.e the speed the core 2 duo offers is enourmous than that of the dual cores... The C2D has more room for Level Cache. Apart from Dual Cores and C2D, Pentium D is nothing but, two prescotts running together side by side.. Its very HOT! So u cant expect more over clocking... but the C2D is made with revolutionary 65 nm fabrication process.... which runs cool and good for overclocking...
Please correct me if i'm wrong
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Today's noobs are tomorrow's geeks. Don't make fun of them.. encourage them. - Gigacore
Any processor having two cores is called "a dual core" processor. Example: Core Duo, Core 2 Duo, Pentium D ,Athlon64 X2 etc.
However Core 2 Duo is a architecture. It is a IC design ,simply put.(Though that would be a gross understatement, to tell an Intel engineer, "Oh ,just an other circuit " )
So it means that in both pentium D and core 2 duo.....There are 2 separate processors running side by side.....But then How does the performance differ,,,????