8. Powerplay 4: Speed To Fit Your Needs, Continued

GUI for performance selection:

The user can choose to turn Powerplay on or off using a setting implemented in the driver.

Additionally, higher 3D performance or longer battery life at the cost of lower graphics performance can be selected using a slider.

User Activity:

Just like and mobile processors from AMD and Intel, the voltage and clock speed can be dynamically adjusted depending on the system load. What AMD and Intel call Powernow and Enhanced Speedstep , ATi calls Power on Demand.

Using the formula

P = C * f * V?

where

P: Power consumption,

C: Total capacity of all gates of the GPU,
f: GPU clock frequency, and
V: GPU voltage supply, the power consumption P is directly proportional to the clock frequency f and proportional to the square of the voltage V. From this formula, it is evident that the most effective way to lower power consumption is a combination of reductions in clock speed and voltage.