970 is a real beast; if your into the future technology you should look into the R9 290x. Mantle seems like it will be widely used. Both cards are around $350. As for a motherboard, I use a
Gigabyte ATX Socket AM3+ AMD 970 Chipset 2000MHz DDR3 SATA III 6Gbps Ready AMD 9 Series FX Motherboards GA-970A-D3P.
It allows for some overclocking, which is a must, as you have the FX 8350/8320. I have the 8320 overclocked to 4.4ghz with a cheap Evo 212 cooler.