Use Amdahl's law to illustrate why it is important to keep a computer system balanced in terms of relative performance between for example I/O speed and raw CPU speed.
Amdahl's law: system speedup limited by the slowest component:
Assume 10% I/O
CPU speedup = 10 =) System speedup = 5
CPU speedup = 100 =) System speedup = 10
I/O will more and more become a bottleneck!