A Core 2 quad is essentially 2 Core 2 duos put on one chip so its almost twice the power.
The quad core processor has four cores. It is essentially two of the Core 2 Duo processors as the Core 2 Duo only has two. The quad core will be faster and as a result more expensive.
To be blunt, the Core 2 duo has two proccesing cores while Core 2 quad has four proccessing cores.
There is no difference between dual core and core 2 duo. Intel just name its recent family of dual core processors as "core 2 duo". Both (core 2 duo and dual core) works in same fashion.
the Intel core 2 quad
The quad core is better. As its 4 cores, the workload is spread efficiently between them so it runs smoother. But the quad core is more expensive.The Intel Core 2 Duo processor was designed to meet the demand for increased performance from PC users. It can run multiple, intense software applications simultaneously.
The Athlon x4 will be better as it is a quad core compared to the Core 2 Duo's dual core technology. Should you wish to look at the Core 2 Quad, then the Core 2 Quad would be a better choice.
The difference is in the processors. Intel's processors are named Core 2 and Core i5. The i5 is a bit faster because it is a quad core, while the core 2 uses only 2 cores.
There is absolutely no difference. They are simply branded differently. A "Centrino" processor is any Pentium M, Core Solo, Core Duo, Core 2 Solo, Core 2 Duo, Core 2 Quad, ore Core i7 coupled with an Intel chipset, wireless card, and integrated graphics.
Core 2 duo is dual core. And before that was core duo which was dual core too...
From an AnandTech article the answer appears to be 582 million transistors for the Quad, 291 million for the Duo. Reference: http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2866
i think cure 2 duo is best
The Intel P45SG can support the Core 2 Duo and Core 2 Quad, and is an all-around solid board.