All desktop Core i7 CPUs are quad core CPUs. However, only certain mobile Core i7 CPUs are quad core CPUs while others are dual core CPUs. All “M” and “U” model Core i7 CPUs are dual core CPUs while MQ, HQ and MX versions are quad core CPUs.

Core 2 duo has better performance than Dual core as it has better overclock ability than Dual core. In this processor we can overclock the CPU up to 3.12GHz (approximate value). In Core 2 Duo processor we can overclock it up to 4.0GHz.

Dual-core processors can get a better battery life and higher clock speeds when compared to a multi-core processor. A 3.8 GHz single-core processor can be more beneficial than a 1.8 GHz dual-core processor when a single task is to be performed. Hence some programs cannot be run on a dual-core processor.

A dual-core processor is a CPU with two processors or “execution cores” in the same integrated circuit. Each processor has its own cache and controller, which enables it to function as efficiently as a single processor.

When we talk about gaming, we often recommend investing in at least a quad core CPU. Your system will perform much more smoothly when gaming on a quad core CPU as compared to on a dual core CPU.

Overall, the answer is clear – the Core i3 is the better processor. That doesn’t mean that it absolutely body-slams the Core 2 Duo. The Core 2 Duo isn’t hugely slower. However, the Core 2 Duo is on its way out, and the Core i3 is slightly better in just about every way.

Overall, the Core i3 is a bit faster than the Core 2 Duo E7000 series, and slightly faster than the Core 2 Duo E8000 series in most applications. Note that the Core i3 also has an integrated graphics chip on the CPU, and although it is not very powerful, it is more than enough for office applications.

The dual core processor has two separate cores on the same along with a individual cache memory for them. A dual core processor performs better than a single core. Dual core processor consumes more battery compared to quad core and also gives reduced performance than quad core. A quad core processor has chip with four independent cores.

The Core 2 Duo processors, however, don’t have the same differentiation between versions of the same architecture. The fastest Core 2 Duo desktop processor has a speed of 3.33Ghz, while the fastest Core i3 desktop processor is clocked at 3.06Ghz.