Benchmarks: Power Consumption
The Athlon II X2 250 uses a minuscule amount of power when compared to similar performing dual-core processors. The entire system used just 150 watts under load with the Athlon II X2 250 installed and 115 watts at idle.
In terms of efficiency the Phenom II X2 550 was perhaps even better, hitting 168 watts under load and 134 watts at idle.
Although the Intel Pentium E6300 and Core 2 Duo E7400 were also very efficient, they did consume more power. Finally the quad-core parts proved to be very power hungry when under load while the Phenom II X4 910 was quite reasonable when at idle.