The stability analysis of a slide drive servo system of numerically controlled machine tools is important to improve its performance, but is very difficult since an actual system has a lot of nonlinearities. When the slide of the system is driven, the analysis is much more difficult because of stick-flip phenomena etc. In this paper, a semi-graphic solution method using describing functions is proposed, which is similar to the one proposed in the 1 st paper in which the slide is not driven (1) But, in this paper, particular treatments are given to frictional nonlinearities and digital quantization nonlinearities because the slide is driven. By using this method, the nature of stability and the mechanism of self-excited oscillations (containing stick slip) observed in the actual system are clearly explained. The analysis and experiments are done on the software servo system in which a mini-computer is used as a digital controller.