An electrosurgical system includes an electrosurgical probe connected to a control console, wherein the probe is capable of coagulating and ablating tissue depending on a selected operating mode. Before operating the system, probe-specific data stored in a memory device associated with the probe is read by a processing device in the console. The data includes source impedance values specific to a coagulation or cutting mode of operation. A constant duty cycle value for a modulated cutting mode also is provided. Depending on the operating mode selected, an RF generator adjusted to have a predetermined source impedance value provides a voltage value to the probe. During the duty-cycled mode, the RF generator generates an instantaneous voltage value output for a duty cycle portion that is less than 100% of a time period, which value is no less than a maximum continuous average voltage value for the electrosurgical probe.