The 3960X has 24 cores and 48 threads, something you wouldn't see previously unless you were using a Xeon or other server class hardware. Still, as the maximum temperature is 95*C, 77*C 24/7 is perfectly fine.
I figured you had to be packing some serious cooling to keep that beast cool. You could always try to manually "overclock", trying for 4.2 or 4.3ghz on all cores with a lower voltage. To quote Anandtech on their 3970X, they were able to get 4300mhz all core on 1.35v and 4200mhz on 1.3v, both times resulting in higher performance, lower power consumption, and lower temperatures than with PBO active, not surprising as AMD is very aggressive in the voltage department. They were using a Thermaltake Floring 360 in their setup.
Even if you were able to shave off 25w of power consumption, assuming 24/7 use and 15¢/kWh, that's about $8, which at current prices is a Wendy's Big Chicken Bag and money left over, not to mention quite a bit less heat thrown off.
