Tried the displayer on bot on-board vga and other computers.Changed cables.Problem is the same.While pc isn't open,the blue led light on the screen just turns on and off as normal.When turned on the pc,it doesn't display anything and LED keeps blinking,but the on-time of the LED is gets a lot longer.I succeeded a few times in turning it on by playing with cables.When left the monitor off a minute it gets broken again.What is the possible problems and solutions?