trying to decide on an athlon II x4 processor.

what is the difference between the energy efficient models and the regular models? 

I see the watts are much lower - 45w verus 95w. is that the only difference? 

also, i see the processor speeds for the x3 are higer than the energy efficient x4 speeds.  which spec should i focus on more?  the number of cores or the processor speed? 

thanks

You may as well ask us whether you should go for a lower 0-60 time or better mileage when buying a car. 

It's a tradeoff between power consumption and performance.  Which is more important to you?

 

Individual core speed > number of cores, as there are very few non professional home user programs which can actually efficiently use more than one or two cores.

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