The thermal modulation of a microring resonator with integrated chromium heater has been investigated. It is shown that the modulation speed can be enhanced by optimizing the driving signal, i.e. creating an overshoot and biasing the signal. Measurements at a modulation frequency of 500 Hz showed that by applying an overshoot to the driving signal, the power needed for equal moduation depth can be reuced by 44%. Measurments with overshoot-and -bias driing showed that both rising and falling slopes can be improved.