You can't measure the actual power of one processor and accurately compare it to that of another processor type.
This is because processors like the Pentium, do nearly everything in a completely different way than a PPC processor does. Because of this, there is no set system of numbers that will allow you to accurately evaluate the power of one processor over another by its clock speed.
By and large, the motorola/IBM processors do accomplish more at a lower clock speed (the GHZ or MHZ of the CPU) than their pentium counterparts, this is why the high end pentium chips come at such high speeds, although the latest offerings from IBM and Motorola have a much lower available clock rate, they are still roughly equivalent in terms of processing power. Top of the line on one is *usually* roughly equivalent to whatever the top of the line offering is from the other. With certain exceptions regarding specific applications, and the sometimes long delay in getting updated chips from IBM/Motorola.
The only thing you can do very accurately with a clock speed, is judge roughly how much faster or slower one chip is to another that has the same processor core within it.
outside of all of this academic...
there is no way 1 to 2 clock cycles on a 68k or PPC cpu is going to be able to accomplish as much as roughly 2,000,000 clock cycles on a pentium core.
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Changed some wording for readability
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