I have the Nvidia GTX 760 and that requires a minimum of 500W as does the 970. I firstly tried using a 650W power supply but that was surging in my PC, luckily my motherboard turned the PC off before any damage was done. I now have a 750W power supply by Corsair and everything is running great. I would recommend getting the same Wattage power supply or better if you can afford it. Hope this helps(:
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