A mechanism is provided for minimizing power consumption for operation of a fixed-frequency processing unit. A number of timeslots are counted in a time window where throttling is engaged to the fixed-frequency processing unit. The number of timeslots where throttling is engaged is divided by a total number of timeslots within the time window, thereby producing a performance loss (PLOSS) value. A determination is made as to whether determining whether the (PLOSS) value associated with the fixed-frequency processing unit is greater than an allowed performance loss (APLOSS) value. Responsive to the PLOSS value being less than or equal to the APLOSS value, a decrease in voltage supplied to the fixed-frequency processing unit is initiated.