Intel® Core™ i5- vs core 2 duo - Intel i5 - CPUs

Well a Core i5 is typically a quad core while the Core 2 Duo is a dual core, so the i5 has more cores. As well the i5 is a newer architecture and thus has better performance than the Core 2 Duo. So to answer the question, the Core i5 is better. By a lot.

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