Power Consumption

To measure power consumption we looked at overall system power consumption and tried to keep as many variables static. There are some basic differences which we cannot get around, mainly that the 925X uses lower voltage DDR-II while the nForce4 uses regular DDR, but for the most part our results were quite controlled. We also included power consumption figures from 130nm Socket-939 Athlon 64 3200+ and 3000+ chips, which as you may know, do not exist. The reason we did this was to show the sharp contrast to the power consumption figures of the 90nm 3500+ we've included in the charts below.

We measured power consumption in two states: idle sitting at the Windows desktop and under load while running our Windows Media Encoder 9 test, which proved to be one of the most strenuous CPU tests we ran as it pretty much isolated the CPU subsystem.

The Pentium 4 570J tops the charts as the heaviest power consumer out of our collection of CPUs here, which is no surprise. Since the 570J here is a different chip than the other Pentium 4s, its not too unsual to see slightly lower idle power consumption given that different chips in the Pentium 4 family can have different operating voltages.

We can't wait until AMD brings more of their Athlon 64 chips down to 90nm next year so that we may have an even cooler running Athlon 64 4000+.