I am currently running an SLI setup with 2 watercooled 680's (reference boards from MSI) Up to now experience has been great and the silence was perfect. However I noticed last night when I jumped onto Guild wars 2, that I could hear a buzzing sound come from one of the GPU's. I haven't identified which one yet, if its one or both. When I did a little digging on coil buzz I saw many posters stating that this changed in pitch/noise level by overclocking or underclocking the cards. Applying V-sync also has no effect. In my case I have the same volume or same buzz regardless of OC or stock values. This noise only occurs when in a game, and the moment of closing the game the buzz disappears. I haven't tweaked anything differently to cause this sound to occur aside from my GPU OC which I had been using since watercooling about 2months ago. I also wonder if it could actually be the mobo causing the sound, although this is difficult to locate do to the shield that comes with the sabertooth. Current setup is this Mobo: Sabertooth Z77 CPU: 3570k Memory:Ripjaw 8gb 2133mhz GPU: MSI reference 680SLI PSU: Seasonic ultra quiet 850W Is this scenario above actually the coils acting up? I have even tried to locate the source by using an eraser on certain exposed areas of the GPUs in the hope something was loose, but the buzz remains. any advice would be very much appreciated.