Gone are the days when performance benchmarks settled all Intel vs. AMD processor debates. The tone of the desktop computing world is palpably shifting towards power conservation, and even indivual computer users are starting to wonder "just how much power is this going to take to get me there?"

Perhaps it's only when we consider the 24x7x365 electrical operating cost of a computer that these small power reductions muster any significance, but there it is. In a sense, what's happening now parallels the transition to from loud computers to the silent PC esthetic. Before hot-running computer processors went quiet, enthusiasts' attempts to reduce the PC noise were exceptions to the rule, rather than the norm. An entire industry now thrives on selling quiet computer hardware, could the same hold true for energy efficient desktop processors that don't sacrifice performance?

I think we're all still finding our feet on the energy efficient component, but it's certainly a new component PCSTATS will be considering as we mull over the benchmark results of the Athlon64 FX-62 and X2 5000+ processors. Now, let's get on with the total system power draw tests...

Total Power Consumption Tests

The price of energy is increasing world wide, and any reduction in the amount of power a CPU requires is welcome. Wading through the technical numbers that Intel and AMD provide can be confusing because each company reports values in slightly different ways.

On paper AMD appears to consume more power since its values are higher, however AMD lists its maximum power usage while Intel posts typical. Obviously the two are not comparable and to find out which actually consumes more power, we decided to test things out.

Representing Intel will be a retail Intel Pentium D 840, Pentium 4 540, and Pentium D 940 processor. Standing in for AMD are the socket AM2 Athlon64 FX-62, Athlon64 X2 5000+, and socket 939 Athlon64 4000+ and Athlon64 FX-60 processors.

The test specs for each system stayed as constant as possible: Akasa PowerPlus AK-P550FF power supply, Western Digital 74GB Raptor hard drive, an 8x Gigabyte DVD-/+RW drive and a MSI NX6600GT-TD128E videocard. Please note that Cool 'n' Quiet is disabled for these tests, with Cool 'n' Quiet enabled, total system power draw will be even less that what is reported. A picture of the total system power draw test configuration is shown at right. The Extech Power Analyzer is located between the mains 120AC supply and the PC power supply.

To simulate single-core load, the Prime95 Small FFTs test was run, and two instances launched for dual core loading. Total system power consumption was read with a Extech Power Analyzer Datalogger (model 380803) for both CPU loaded and CPU idle states. Please keep in mind that these values are measuring an entire system while the processor is running under computational load or idle.

How do the socket AM2 Athlon64 FX-62 and X2 5000+ impact total system power draw? Let's have a look....