Before upgrading your graphics card, Id
highly recommend upgrading your CPU/Motherboard. The reason I say this is because with a FX-6100(Or really any AMD CPU for that matter), your not going to get the best possible performance than you can out of a 970, Or even a 960.
Heres an Intel Skylake i5-6400, and An ASUS Z170 MB that I chose along with it(you can pick any HI70/Z170/B-Series chipset board, this is just what I considered to be the best value for your money):
http://www.newegg.com/Product/Produc...64&ignorebbr=1($189.99) [CPU]
http://www.newegg.com/Product/Produc...91&ignorebbr=1 ($105.99) [MB]
Total: $295.98 W/ 4-7 Day shipping