Why CPU Frequency Stalled
Philip E. Ross · IEEE Spectrum · 2008
In this paper, the cycle rate of the PC's central processing unit has been described. CPU clock rates peaked a few years ago and they aren't a very useful key to chip performance anyway. The clock keeps a processor's parts working in unison. The clocks are not worth the cost in terms of power consumed and heat dissipated. Intel calls the speed/power tradeoff a "fundamental theorem of multicore processors" and that's the reason it makes sense to use two or more processing areas, or cores, on a single chip.