Suppose you are choosing between four different desktop computers: one is Apple MacIntosh and the other three are PC-compatible computers that use a Pentium 3, an AMD and a Pentium 4 processor respectively.

Which of the following observations are true? Justify your observations.

The fastest computer will be the one with the highest clock rate. Among the three PCs since they use the same Intel-compatible instruction set and execute the same number of instructions for a program, the fastest PC will be the one with the highest clock rate. Since AMD uses different techniques than Intel to execute instructions, they may have different CPIs. But you can still tell which of the two Pentium-based PCs is fastest by looking at the clock rate. Only by looking at the results of benchmarks for tasks similar to your workload can you get an accurate picture of likely performance.