A display apparatus includes a first communication port to receive a first video signal, a second communication port to receive a second video signal, a display unit, a first video signal processor including a first synchronous signal processor to check whether a first synchronous signal of the first video signal is inputted, a second video signal processor including a second synchronous signal processor to check whether a second synchronous signal of the second video signal is inputted, and a controller to disable the first and second video signal processors and to alternately enable the first and second synchronous signal processors according to a predetermined check time to check whether the first or second synchronous signal is inputted in a power saving mode.