I currently have 1 evga gtx 970 sc (blower style card) and I am upgrading my cpu to a ryzen 1700 on an asus crosshair vi board. My psu is an 850 watt gold rated psu. I was thinking about getting another 970 sc for $160 to improve performance since games these days are recommending at least 1 970 and DX12 is aiming for better multi-gpu performance. What do you guys think? Would I get acceptable performance increases? Would it be worth it in the long run? Should I save my money and buy a single better card in the future?