Yes. Most GTX 970's, for example the Nvidia reference model and the EVGA FTW, only require 2x 6 pin connectors. The requirement varies between different brands of the GTX 970. (The Asus Strix version requires a single 8 pin power connecter.) What kind of GTX 970 will you buy? Your 1000w PSU is more than enough for a GTX 970.