good cpu and mobo choices. Your mainboard does not influence OC'ing the gpu (That's coz it is a chip with it's own mobo (the PCB) and all OC features and capabilities are present on the gpu pcb.) The things that will limit your gpu OC are:
2. PCB design
3. Cooling (Stock or aftermarket)
you cant do anything about PCB design and not much about the Cooling either (stock coolers are good enough anyway). Make sure your PSU is the right power rating to handle 6 pin power connector for the gpu.