The story is presented to put the focus on the Haswell processor itself, and there will be saving there for sure. But I would expect that a good part if not mos

The story is presented to put the focus on the Haswell processor itself, and there will be saving there for sure. But I would expect that a good part if not most of the savings will come from the platform surrounding the processor. Intel has a lot of control there too, they also provide the chipset and define the requirements for the whole platform that ODMs then follow. The PC platform for now is very inefficient. It uses standards with low power support, but typically a lot of elements are left always on and just waste power just because it is easier and up to now was not a big deal. But with the constant reduction of the CPU part now it becomes important to dynamically turn off the rest of the platform as much as possible, and not only the CPU internals. It's a given in the ARM world, and my understanding is that Intel finally brings this mindset to the PC with the Haswell platform. Which is very good and about time! An example: the USB protocol defines Link Power Management, which allows to very dynamically put a USB link in low power (switch time is ~10 us). Supporting it will become required with Haswell from an old IDF presentation (that I've lost, so no link). Another example: optimizing the voltages generation to avoid waste. We know part of it has been pushed into the chip with Haswell so for sure Intel looked into the whole thing. This is obviously useful for laptops and tablets, but I would love to see this done thoroughly in mini-servers and HTPC devices. An x86 server doing nothing can burn 10 to 20W easily. A whole ARM tablet use less! I would love to see this reduced (out of principle, but also less heat and noise). It can touch most part of the system and could be extended in time. For example in an ARM SoC for mobile it's possible to cut the internal display link between AP and LCD display if the image displayed doesn't change (the controller on the display locally cache the image). That saves the power from transferring data from the AP to the display over a high bandwidth external interface. That kind of thing could in time come to external display links. The goal is to go all over the system with a fine comb, and make sure that when nothing happens no energy is wasted. We'll see how big a step the Haswell platform make in this direction, but it'll likely take several iterations.