I definitely have a significant amount of coil whine on my 1070 sc while playing certain titles. Seems to be things that only put a medium amount of stress on the card that lead to this. Desktop (very low fan), and something like 4k Gears 4 (High fan) don't seem to encounter it. It's very loud though, to the point where I'm actually avoiding playing certain games where I know it will be an issue.
I'm in the process of a step-up right now (though who knows, that might take many more months to happen apparently), so I'm sitting here with my card, wanting to RMA it, but also thinking that might cause additional issues when it comes to the already super long step-up process.
It's very unfortunate.