There are alot more compatible motherboards out there. Be sure to get one with the AMD A88X chipset for the X4 860K, with other (older) chipsets you need to flash the bios before the motherboard can recognize the X4 860K and be able to boot.
The X4 860k is the best cpu on the fm2+ socket, it is an A10 7850 without the integrated graphics. It has no problem when coupled with a R9 270. As usual overclocking the cpu can give even better performance in cpu-intensive games.
There are alot more compatible motherboards out there. Be sure to get one with the AMD A88X chipset for the X4 860K, with other (older) chipsets you need to flash the bios before the motherboard can recognize the X4 860K and be able to boot.