As long as I used my VGA cable, my LCD monitor worked fine. But when I switched to my DVI cable, sometimes my monitor turns off. When it happens the power light still on, the screen is dark but the very darkened images can be seen in certain angles in certain circumstances, so I supposed that just the backlight has turned off. I presume it's the cable or the connectors fault, but I am asking here if you had a similar experience, and if the only solution is to buy a new cable.
My monitor has both connections (VGA and DVI) but my video card has only DVI. So when I used the VGA cable I used with an adapter between it and the video card.
** UPDATE ** It wasn't the cable. I switched back to my old VGA cable and it is still with problems.