The most beastly of all GTX 680s.
The N680GTX Lightning was designed with extreme overclocking in mind, however not everyone will have access to LN2 cooling. Even still, turning the BIOS switch from ‘Normal’ settings to ‘LN2’ setting will allow MSI Afterburner to increase the voltage headroom from a limit of +133 to +200mV.
Using this setting I was able to bump the core clock speed from 1110MHz to 1210MHz, while memory clocked was bumped from 6008MHz to 6108MHz (effective), resulting in an actual overclock of 9% on core clock and 1.6% on memory speeds. Your mileage may vary.