First of all make sure it is your video card and not the display or a disconnected cable or something like that. If it is the video card then the whole motherboard will most likely have to be replaced. On most laptops you can't replace the video card seperate from the MB.
Then if it is still under warranty RMA it or whatever you have to do to get the warranty service. The site says 1 to 3 year warranty so if you bought it in the past year it is most likely under warranty.