Surely, no more Core 2 Duo. They are still all over the place as are Celerons, but they are aimed at the low end of the market.
I bought and i7 machine to get a hyper threaded quad with turbo (built in overclock determined by Intel)
I bought an i5 to get a hyper threaded mobile
dual core on a minimum die (for heat) in a laptop with turbo.
When I bought, i3's were dual core, but no hyper threading which I think they have now, and no turbo about which I do not know.
So, those are factors: quad vs dual; hyper threading; turbo.
If it's for a laptop, try for 25 nanometer, but if it is any mobile processor, it should be O.K. In a laptop, the question is heat.
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