OLD lcd white display new lcd no display at all

Hi,

i have very strange problem with the laptop.Laptop was not turning on when i open the motherboard and remove the LCD cable Laptop start turning on so i think it may be the cable after changing cable LCD came on but white display came.So i think may be new cable is faulty replaced from working laptop still white display then i tried new lcd screen here is strange thing happened no display on new screen tried couple of working screens but no display at all on old LCD it's shows white display.If anyone know what can be the problem plz help me to solve this problem

Thanks