Quad core is the best for long lasting performance...dual core is good for gaming, but if you like multi-tasking you can't beat quad. Idk about laptops but the overclocking potential of the desktop ones are amazing, you can hit around 3.4-3.6ghz on Air cooling which is pretty amazing for having 4 cores.
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Inferno Package/CAI/180tstat/3" DP/AL 104 XP's/3.8 MPS/Tuned