Without a doubt you should overclock that beast. Get one of the Noctua heatsinks if you case has good airflow. If not, get the Corsair H50.
I don't know how well the performance will be with just one 460.
If you were to get two of them and use SLI it would be without a doubt easy to run anything at 1920x1080.
However, you'll probably need to get a stronger PSU to go with it as well.