Although AMD used contemporary 45 nm process for manufacturing of their Phenom II X4 processors, the power specs of these solutions didn’t go down to the level of Intel offerings with analogous performance. However, it is still too early to draw any final conclusions yet, because the new Athlon II X4 CPUs feature a new smaller core, which can in fact affect their heat dissipation and power consumption readings.
Therefore, we were especially interested in the results of our power consumption tests of the new AMD processors. The following numbers show the total power consumption of the full tested platforms (without the monitor). During our tests we used 64-bit LinX 0.6.3 utility to load the systems to the utmost extent. Moreover, to ensure that we estimate the power consumption in idle mode correctly we activated all power-saving technologies, such as C1E, Cool'n'Quiet 3.0 and Enhanced Intel SpeedStep.
Unfortunately, even in idle mode Athlon II X4 can’t compete against Intel processors from the same price range and with similar performance, just like other 45 nm AMD CPUs. However, the power consumption difference between the tested systems in idle mode is not big enough to allow us to draw any definite conclusions.
The situation looks considerably worse for AMD under heavy workload. When we tested Core 2 Quad Q8000 processors back in the days, we were amazed at their energy-efficiency. Not that much has changed since then, AMD Phenom II X4 and Athlon II X4 can’t get anywhere close to the same power readings. Despite the fact that Propus processors proved much more economical than their Deneb based predecessors, the difference in power consumption of systems based on Athlon II X4 630 and Core 2 Quad Q8200 reaches almost 50 W!
To get a fuller and bigger picture we also measured the power consumption of Athlon II X4 processors under load, separate from the rest of the computer components. To be more exact, we measured the power consumption along the 12 V power line connected directly to the processor voltage regulator on the mainboard. In other words, this approach didn’t take into account the efficiency of the processor voltage regulator.
The obtained results once again prove everything I have just said. If you are concerned with the power consumption of your system, then AMD processors that do not belong to the energy-efficient type should be taken off the list of choices right away. Although Athlon II X4 also have 95 W TDP, just like Core 2 Quad Q8200, in reality these CPUs cannot be compared at all in actual power consumption. AMD solutions consume about twice as much, but unfortunately, do not offer the same performance advantage. As a result, Athlon II X4, just like Phenom II X4, lose hopelessly to their competitors in performance-per-watt.