A power control apparatus includes a processor configured to collect first information related to operation of a performing unit configured to perform data processing and information related to operation of a bus configured to transfer data; determine an operating frequency and an operating voltage for the performing unit, based on the collected information; estimate based on the collected information, a period elapsing until the performing unit suspends operation and a period elapsing until the bus suspends operation; derive a discriminant that obtains a difference of total power consumption and power consumption pre-switching; and execute a switching of an operating frequency and an operating voltage of the performing unit, based on a value of the discriminant.