I have the following question:

A cell phone performs very different tasks, including streaming music, streaming video, and reading email. These tasks perform very different computing tasks. Battery life and overheating are two common problems for cell phones, so reducing power and energy consumption are critical. In this problem, we consider what to do when the user is not using the phone to its full computing capacity. For these problems, we will evaluate an unrealistic scenario in which the cell phone has no specialized processing units. Instead, it has a quad-core, general purpose processing unit. Each core uses 0.5 W at full use. For email-related tasks, the quad-core is 8 as fast as necessary.
a. How much dynamic energy and power are required compared to running at full power? First, suppose that the quad-core operates for 1/8 of the time and is idle for the rest of the time. That is, the clock is disabled for 7/8 of the time, with no leakage occurring during that time. Compare total dynamic energy as well as dynamic power while the core is running.
b. How much dynamic energy and power are required using frequency and voltage scaling? Assume frequency and voltage are both reduced to 1/8 the entire time.

Now for part a. I did the the following which I think might be right: I divided the new dynamic energy and power by the new ones so I did [1/2xcapacitive-loadxvoltage^2x1/8]/ [1/2xcapacitive-loadxvoltage^2] which gives me 1/8 so the new dynamic energy is 1/8 the old one.

However, for part b I did (for dynamic power) the dynamic power is proportional to: capacitive-load(1/8)^2x1/8x1/2=capacitive-loadx1/1024

So my final answer was in terms of the capacitive load, how can I get a final answer that is just a number representing the dynamic energy?


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