Methods and apparatus relating to autonomous C state mechanism and computational engine alignment for improved processor power efficiency. are described. An embodiment determines whether a semiconductor package should enter a package C state based on energy consumption values for entry into and exit from the package C state, an amount of time the semiconductor package stayed in the package C state previously, and one or more breakeven time points between the various package C states. Another embodiment detects a delay by an imaging computational unit of a processor to enter a low power consumption state relative to one or more other computational units of the processor. The logic causes the imaging computational unit to enter the low power consumption state in response to detection of the delay. Other embodiments are also disclosed and claimed.