We typically look at the two most extreme conditions for power requirements: idle operation and peak load. It turns out that the power consumption difference of the two test platforms is significantly different, mostly because of the additional Nvidia ION2 graphics on Jetway's motherboard.
Adding 7 W more idle power consumption doesn't seem like a lot, but it makes quite a difference in low-power scenarios. The difference under peak load (CPU-only) is roughly 8 W, showing that the additional power draw is always there and that the faster Atom seems to be consuming slightly more power than the older Atom D510.
Thus, the peak power consumption of the Atom D525 system seems to be roughly 1 W higher than the D510 machine. This could be within the range of error of our test equipment, so we'll call it a draw. Intel's claim of delivering more performance at the same thermal envelope seems valid.
Still, we'd like to compare the two test systems more holistically. In this light, the overall result is different because of the ION2 graphics unit on the Jetway NC98-525-LF. The platform consumes more power, which has a negative impact on efficiency. At the same time, the additional power consumption might be worthwhile, considering that you can easily play high-definition video content. We'll discuss this in the conclusion.
The power required for our single-threaded workload is higher on the Atom D525 system because of its added ION2 graphics unit.
This also applies to the multi-threaded test.
Finally, our total efficiency test reveals that Intel's Atom D510 platform is more efficient than the newer Atom D525 platform from Jetway. This doesn't help to compare efficiency between the two Atom generations, but it shows us that the system with ION2 graphics is less efficient and delivers less performance per watt in standard application workloads.
This is a summary of the full efficiency workload. As you can clearly see, power consumption is quite a bit higher on the Atom D525-based solution for the reasons mentioned above. Power consumption should actually be very comparable between the two, with the Atom D525 delivering better performance that leads to a faster completion of the workload. Looking at the approximately 1 W difference we extrapolated, it's pretty safe to say that performance per watt does not change much on the new Atom D525.