A spindle motor start up method wherein a torque balance between the stator and rotor is broken so as to avoid startup malfunctions, and thereby improve motor startup time in spindle motors prone to startup malfunctions, such as hard disk drive motors having a 4:3 ratio of the number of rotor magnetic poles to the number of stator slots. Processes for breaking a torque balance according to the present invention include: (1) gradually decreasing an initial commutation (switching of each phase) frequency at the startup timing from a frequency higher than a commutation frequency in a conventional startup; (2) gradually decreasing an initial commutation frequency at the startup timing from a frequency higher than a commutation frequency in a conventional startup to a low frequency, and next, gradually increasing the initial frequency from the low frequency; (3) changing a drive current of the spindle motor so as to break a torque balance between the spindle motor stator and rotor; (4) monitoring a back electromotive force detection signal while commutating, and restarting commutation when the back electromotive force detection signal is not detected; and (5) monitoring a back electromotive force detection signal while commutating, resetting the commutation at a time in a commutation sequence after an initial commutation from a first phase to a second phase, and restarting the commutation from the first phase to the second phase.