But, rendering said widgets happens 2 or 4 times as fast, limiting the amount of time spent off idle. Sure, it uses more power and thus creates more heat. But nowhere near the amount that running anything significant at even 600mhz does. That is, playing an mp3 at 850mhz means 5% on CPU, 95% idle. Heat is 5% of maximum dissipation @ 850mhz, so say 3W * .05 = 0.15W. At 250mhz, it means ~15%, plus the occasional bout up to 850mhz anyway. Say the processor draws 0.5W at full load @ 250mhz. 15% of 0.5W = 0.075W, for a difference of 0.075W thermal dissipation. Hardly anything to worry about. It may reduce battery life slightly, but I bet 0.075W pales in comparison to the rest of the power draw (radios, DSP, amplifier, etc). Compare that with running an intensive process at 600mhz. Assume the processor draws 1.5W at this speed. 1.5W @ 100% for 10 minutes represents 0.25Wh of heat dissipation. That's the same as a 5% duty cycle at 850mhz for almost 2 hours. 10 minutes at 600mhz is ~10 times worse. Of course there is the argument that even though the heat dissipation is low, the temperature changes are more rapid and may lead to premature thermal failure anyway..