Performance is not the only practical spec that may be of interest to potential buyers of mainstream CPUs. In many cases their power consumption matters a lot, as it has direct connection not only to the amount of your next power bill. The same parameter sets certain restrictions and criteria when it comes to picking out a system case. Therefore, we decided to add power consumption tests to our performance research.
The graphs below show the full power draw of the computer (without the monitor) measured after the power supply. It is the total of the power consumption of all the system components. The PSU's efficiency is not taken into account. The CPUs are loaded by running the 64-bit LinX 0.6.4 utility. We enabled all the power-saving technologies for a correct measurement of the computer's power draw in idle mode: C1E, AMD Cool'n'Quiet and Enhanced Intel SpeedStep.
All participating systems consume almost the same amount of power in idle mode: the difference between the best and the worst score is less than 10 W. Athlon II X4 based platforms require a little less power. However, the six-core Phenom II X^ 1055T, on the contrary, consumes more than the rest of the participants in idle mode.
However, when it comes to power consumption under heavy load, the differences between tested systems equipped with mainstream processors may exceed 70 W. Note that the worst results here belong to Phenom II X4 and Phenom II X6, which means only one thing: mainstream processors from AMD are not that fit for energy-efficient and quiet systems. Dual-core Intel products for LGA775 and LGA1156 platforms prove to be much more energy-efficient. However, even more power-hungry quad-core CPUs from this maker will offer better performance-to-power consumption rates than AMD CPUs.