The  has a series of icons that graphically represent the current
scaling level of the processor you are monitoring. They are:
IconDescription100% Power
The CPU is running at, or close to, 100% throughput
75% Power
The CPU is running at, or close to, 75% throughput50% Power
The CPU is running at, or close to, 50% throughput
25% Power
The CPU is running at, or close to, 25% throughput
