A driving system of the present invention for use in a displaying device is provided with a pseudo bit-depth extension section. In the pseudo bit-depth extension section, a noise pattern is added to upper-n-bit data of an input signal D0 in m-bit, where (i) m is an integer of 9 or greater, and (ii) n is an integer of 8 or greater, but less than m. Then, upper-n-bit of data D1 thus obtained from the D0 is outputted, as output data D2, from the pseudo bit-depth extension section. The driving system is further provided with an overshoot-driving section for carrying out an overshoot-driving with respect to each of pixels. A noise amount of the noise pattern is 1 or less in 8-bit data, and a calculation in the overshoot-driving section is carried out with n-bit data. With this driving system which adopts a combination of (a) a overshoot-driving method for enforcing liquid crystal to respond at a high speed, and (b) a bit-depth extension technology in which a number of grayscales is increased by adding noise, it is possible to provide, at a low cost, a high-definition displaying device such as a liquid crystal display, having a high-response-characteristics and a high quality of grayscale reproduction.