Power, temps and noise
Comparing reference to reference, the GTX 770 pulls a few extra watts when under load. The 232W figure is about the same as the GTX 780, which is a bigger, wider GPU.
Another by-product of Nvidia's GPU Boost v2.0 is the automatic temperature setting. The GPU aims for the highest frequency when at 80°C or so.
Top marks, again, to Nvidia's cooling solution. The card is practically silent when running under genuine 3D load.