Power And Temperature Benchmarks
At stock speeds, the $1,500 Core i7-920 system uses relatively little power and is in the same league as the $1,000 Phenom II X3 720 system. But when overclocked, the Core i7 machine is significantly more power-hungry. The overclocked/core-unlocked Phenom II X3 720 build doesn't really require a tremendous power increase over its stock draw, but it does consume more.
The $1,000 system's temperatures remain quite low, even when overclocked. But the $1,500 machine's components do appear to build up a lot more heat, especially when overclocked.