Editing Overclocking

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<pre>CPU power consumption (without constants) = leakage + capacitance + switching = voltage^2 + frequency + (voltage^2 * frequency)</pre>
<pre>CPU power consumption (without constants) = leakage + capacitance + switching = voltage^2 + frequency + (voltage^2 * frequency)</pre>
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One factor reducing CPU lifetime is the current it is running with [[:wikipedia:Dynamic_frequency_scaling|dynamic frequency scaling]].
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One factor reducing CPU lifetime is the current it is running with.
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<pre>CPU dynamic power consumption = capacitance * frequency * voltage^2</pre>
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<pre>CPU dynamic power consumption = capacitance * frequency * voltage^2</pre> ([[:wikipedia:Dynamic_frequency_scaling]])
As can be seen from the formula, lower voltage plays greater part in CPU consumption than frequency. By reducing the voltage the damage of overclocking can be reduced and the battery life time extended. Alas, this claim only holds true for architectures not regulating the real voltage and current in special on chip regulators, like OMAP is known to do for almost every gate in their CPU and other SoC function blocks. TI calls this feature SmartReflex™ and lowering the voltage applied to the whole SoC, like suggested here, only reduces the voltage drop across these regulators, thus no positive effect on [[:wikipedia:Electromigration|electromigration damage]] caused by overclocking is to be expected.
As can be seen from the formula, lower voltage plays greater part in CPU consumption than frequency. By reducing the voltage the damage of overclocking can be reduced and the battery life time extended. Alas, this claim only holds true for architectures not regulating the real voltage and current in special on chip regulators, like OMAP is known to do for almost every gate in their CPU and other SoC function blocks. TI calls this feature SmartReflex™ and lowering the voltage applied to the whole SoC, like suggested here, only reduces the voltage drop across these regulators, thus no positive effect on [[:wikipedia:Electromigration|electromigration damage]] caused by overclocking is to be expected.

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