Power Consumption And Efficiency
System Power Consumption at the Plug
The new entry-level quad-core is not capable of beating the Phenom II X2’s system idle power of 82W on our test system. It is still slightly lower on power than the current top model, but the conclusion here is clear: you don’t save idle power by purchasing a simpler processor in the case of the AMD platform.
The situation is entirely different at peak load. AMD’s top model is a power hog compared to the two others. The new Athlon II X4 620 is relatively low on power given that it can stomp dual-core CPUs once the applications are optimized to take advantage of four processing cores.
The total power required for a full PCMark Vantage run is lowest on the Athlon II X4. This test does not consider performance at all.
System Power Efficiency
The average power required during a full PCMark Vantage run was slightly lower on the new Athlon II X4 620 than on the dual core Phenom II X2 550.
Bottom line: stripping away the L3 cache from the Phenom II makes the resulting Athlon II an efficient product when looking at PCMark Vantage performance per watt. Just keep in mind that we aren’t comparing at the same clock speeds, so this statement only applies to the CPU models and speeds we examined.