With C-Ray, the test where the AMD FX-8150 Bulldozer was actually competitive with the Intel Core i7 3770K Ivy Bridge, but the i7-3960X reigned supreme, the power results were interesting.
The AMD FX-8150 delivered more than twice the performance-per-Watt of the i7-3770K Ivy Bridge when running at stock speeds. However, for this very multi-threaded test, the Intel Core i7 3960X beat out both the FX-8150, i7-3770K, and all other processors in terms of power/performance efficiency.
The Intel Core i7 3770K with a stock Intel heatsink fan at its stock speeds was running at around 65°C for this ray-tracing test that takes advantage of all available cores. The AMD FX-8150 and A8-3870K results for the CPU temperature are very low; except that this temperature monitoring using the "coretemp" kernel module was wildly inaccurate most of the time for the AMD CPUs, so take the AMD thermal results worth a grain of salt.