Well, they FORCE the use of the C states to save power, even if the
kernel doesn't want to because it still has runnable tasks. This can be
useful if you know you are running a task that busy waits but would not
suffer from having the performance of the cpu cut in half. Since it is
busy waiting, the kernel never activates the C states, but the
throttling will force it and thus, save you power and heat.
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