5. When You Need To Be "Cheap" With The Battery Power, Call In The PowerMizer, Continued

In the past, is has been hard to verify these claims of power management. Until now! We were able to use an inline test device to see the actual performance difference between the various PowerMizer settings.

This is the inline power adapter that allowed us to tap in and monitor what benefit or lack of benefit exists across PowerMizer's various settings in real time.

To test PowerMizer, we placed an amp meter between the AC adapter and the notebook, using our in line test device to monitor the current draw of the notebook while it is operating. The amp meter was located between the AC power adapter and the notebook, which allowed us to montor the total system current draw in real time. During these tests, we removed the battery, so the charging circuitry had no effect on the results. The amp meter allowed us to monitor the amount of current that is drawn by the system amps. All current that is being drawn by the laptop is able to be monitored by the amp meter, as there is no battery installed. With the test adapter installed and battery removed, the system throttles itself back to 1.2 GHz just as it would if it were running from battery. To monitor our results, we run the first scene of 3D Mark 2002, which in this case provides an ample opportunity to monitor the system. In order to better understand the effects of PowerMizer, examine the following:

With PowerMizer in the MAX performance setting, the GeForce4 Go operates at maximum current draw. The total system current was 2.1 amps, the AC adapter was 20 volt DC power source. To obtain the total power consumption, you would multiply amps by volts, which gives you the total power consumption in watts. We can then take our total of 42 watts and divide it by 37.4, our total watts in the middle (balanced) settings. We then arrive at a total of 12.3% difference between the maximum and balanced settings.

Max Performance - 2.1A * 20V = 42W - (42 / 37.4) - 1 = 12.3%

With PowerMizer in the middle (balanced) setting, the GeForce4 Go is operating in a balanced mode of current draw. The total system current was 1.87 amps, the AC adapter is 20 volt DC power source. To obtain the total power consumption, multiply amps by volts, which gives you your total power consumption in watts. We then take our total of 37.4 watts and divide it by 33.6, which is our total watts in the max battery setting. We then arrive at a total of 11.3% difference between the balanced and maximum battery life settings.

Balanced (Middle Setting) - 1.87A * 20V = 37.4W - (37.4 / 33.6) - 1 = 11.3%

With PowerMizer in the max battery saving mode setting, the GeForce4 Go is operating in a battery saving mode of current draw. The total system current was 1.68 amps, the AC adapter is 20 volt DC power source. To obtain the total power consumption, multiply amps by volts, which gives you your total power consumption in watts. To understand the difference in the PowerMizer settings, we can now compare max battery to max performance. We take our total of 42.0 watts and divide it by 33.6, which is our total watts in the max battery life setting. This allows us to arrive at a total of 25% difference between the maximum battery and maximum performance setting.

Max Battery - 1.68A * 20V = 33.6W - (42 / 33.6) - 1 = 25%

We have provided a graph to help you compare the three PowerMizer settings:

During the testing process, we were able to verify a reduction in current draw by monitoring readings during various states of use. In the balanced mode, we saw about an 11.3% reduction in required power. In the maximum battery saving mode, we saw about a 25% reduction of power. When operating at a low 1.575 volts, using PowerMizer becomes helpful in gaining additional battery life. Although 25% might sound like a big number, it doesn't translate into 25% more "real world" battery life.

As we show in our benchmarks, in certain situations PowerMizer has little or no effect with certain applications. PowerMizer does save power, but depending on the applications you use, your mileage may vary.