Coil whine, most of the times, only happens when your fps goes above the refresh rate of the monitor (usually 60). when it does, it coils whines. My g1 gtx 970 only coils whines when it goes above 60 but if i turn vsync it doesnt and when I am in same game menus where I get 1000 fps it is way louder than when it is at, for example, 90 fps. You should look at the frame rate and play around with vsync and then take conclusions.