The apparatus and method for displaying video data are disclosed. Reference refresh frequency and/or time may be predetermined or derived from predetermined values. Measured refresh frequency and/or time of display panels may be determined and compared against the reference refresh frequency and/or time. Based on the comparisons and through one or more control loops, display properties of the display panels may be adjusted so that one or more display panels may be in sync with respect to their refresh timings without dedicated hardware or a common hardwired synchronization signal.