A display device includes a display panel and a driving voltage generator. The driving voltage generator generates a first quarter power voltage and a second quarter power voltage. The first quarter power voltage has a level between a power voltage and a half power voltage. The second quarter power voltage has a level between the half power voltage and a ground voltage. A data driver alternately outputs the first quarter power voltage or the second quarter power voltage and a data voltage to the data line. A signal controller controls the driving voltage generator and the data driver. The signal controller includes a pattern recognition unit determining an image pattern of an image based on an input image signal. The signal controller controls the driving voltage generator to adjust the levels of the first quarter power voltage and the second quarter power voltage, based on the determined image pattern.