Thank for your reply I really appreciated, I already tried to unplug the cable connection between monitor and video card., and the monitor turn on into "no signal connection" but the monitor still blinking(filicker), as I observed the screen of the monitor became smaller than the original size then it back to their natural size,this is happen in half a second that why the screen is look like blinking., the text and color is clear but the only problem is flicker, I found something about the sound of monitor before when I open the monitor it's only 2 click sound then they open but now is different, 2 click sound and sound like folding plastic. what is the possible part of the monitor is suspected.
Thank you for your reply