Some info here:
http://www.tomshardware.com/forum/254263-29-heat-issue
That spec says 72.7, but that's at the heat spreader. If HWMonitor is measuring the core (inside the CPU), then you can add 5 degrees to that for a max of 77.7, which you are under but very close to. It's probably a stock cooler though so that's to be expected.