Our tests confirmed that Phenom II X3 processors can compete with dual-core competitor solutions when it comes to price-to-performance. Another important integral characteristic of a triple-core AMD processor is performance-per-watt and, frankly speaking, it is of some concern to us, because the core of these processors is much more complex than the Core 2 Duo core. Namely, semiconductor Deneb die that is also used for Phenom II X3, consists of 758 million transistors, while Wolfdale core used for Core 2 Duo CPUs features only 410 million transistors. So, no one expects triple-core AMD processors to prove very energy-efficient. However, to complete the picture we decided to measure the power consumption of a complete system (without the monitor) based on a Phenom II X3 720 processor. We will also compare the obtained results with the power consumption readings taken from other platforms built on processors with similar performance levels.
During our test session we loaded the CPUs using 64-bit version 25.7 of Prime95 utility working in “In-place large FFTs” mode. Moreover, to guarantee correct power consumption readings in idle mode we activated all power-saving technologies, such as C1E, Cool’n’Quiet and Enhanced Intel SpeedStep.
Our concerned proved absolutely justified. Phenom II X3 processors have pretty high power consumption levels although they use cores manufactured with contemporary 45nm production process. Phenom II X3 720 processor consumes considerably more power than 45nm Intel CPUs with two as well as four computational cores in idle mode as well as under maximum load.
So, unfortunately, we can’t recommend the solutions from this processor family for energy-efficient and quiet systems. The competitor CPUs proved to be much better fit for this application.