You can do the diagnosis yourself. Get a new video card (buy one, you can return it if you don't need it). Swap out the video cards and if the problem goes away then your set. If not try a different monitor. If that doesn't work then you got other problems and I'd take it to a shop.
Does it have a Nvidia card? http://laptoping.com/nvidia-mobile-video-graphics-card-problem.html Also, try hooking up an external monitor to the laptop and see if it still happens. If so it's the video card.
I just flashed the bios, and I havent had the problem.. YET.. Lets see. If it happens again, it will go for a repair.