To answer your question it is quite tricky to comprare mac processors to pc based ones. Macs generally use RISC chips (reduced instruction set computer) these chips have limited intructions so the execution of the instructions is generally faster becuase the instructions are simple and there are less instructions for the CPU to look for. Most PC based systems used CISC (complex instruction set computers) which has a large number of instructions, which odviously takes longer to find and execute.

That is why it is hard to compare the speed of porcessors. Hope this helps your question. :)