Open CCC and somewhere in the display configuration for your monitor, ensure that there is no over/underscan. For some reason my CCC had a small degree of underscan turned on which led to the black bars you mentioned.
A word of caution, when you start your games up and pick the native resolution the underscan may show up again. Just turn on any options for windowed mode and/or full screen and then turn off windowed mode again and the black bars should go away. Hope that helps!