It all depends on if your software is optimized for multi core or not. It will be very fast if your software can use all the cores or you run a lot of programs simultaneously. however if your programs don't take advantage of all the cores the clock speed is lower so it would probably be slower.
It all depends on if your software is optimized for multi core or not. It will be very fast if your software can use all the cores or you run a lot of programs simultaneously. however if your programs don't take advantage of all the cores the clock speed is lower so it would probably be slower.
Not necessarily. The core i7's Turbo Boost will make a difference here. If there's not enough stuff going on to make use of all 4 cores, it can switch them off to save power and boost the clock speed of the other cores if the situation demands it (CPU intensive application for example). For the 2.0 quad core, it can get up to 2.9ghz with 1 core active, 2.8ghz with 2 cores active and can boost up to 2.6ghz with all 4 going.
That's not even getting into the differences in architectural between a CPU 3 generations old ( core 2 duo ) and the lastest tech. Clock speed is mostly irrelevant these days when comparing chips across CPU generations.
It will perform better, no matter how you slice it.