Similarly, underclocking or "clock throttling" is the practice of running the clock rate of a processor slower than it is designed. This is used to reduce system power consumption when higher performance is not needed, and used as a safety measure to reduce heat generated by the processor when higher performance is needed. Most processors will automatically underclock when the temperature approaches its thermal limit with safety margins. In this case, the processor reduces its performance to stay within its thermal limits. More accurate temperature measurements allow a system to get closer to its thermal design limit, thus reducing the amount of underclocking and optimizing performance.