I recently bought this graphics card (sapphire dual x r9 270x), about one week ago and I was having this problem that my screen would occasionally flicker slightly. It was only once every now and then and it flickered only slightly so it didn't bother me that much. However today I was using my pc and the screen went black, mouse and keyboard also stopped working. Restarting the pc helped but later, as I was using it the screen all of a sudden went black with some flashing spots and weird lines. Can somebody tell me what's wrong with the video card I basically just bought?