We didn't have nearly enough time to conduct battery life testing. However, we were able to measure the power consumption of a couple of tablets—one based on Clover Trail and the other on Bay Trail—at the battery connect point.
What we saw was very similar power consumption from one generation to the next. Both tablets tended to idle at about 2 W of power draw, and both used 3-4 W during video playback. Total system power draw is probably a bit higher during CPU- and GPU-intensive workloads, but we didn't get any full-platform power use numbers for such scenarios.
We also got a look at the individual power consumption of our tablets' graphics and CPU components in two scenarios: gaming and SunSpider testing.
While gaming, the Clover Trail system's graphics drew about 650 mW, and the CPU drew 700 mW. The Bay Trail system's total power use wasn't far from Clover Trail's, but the mix was very different, with 1.2W going to the IGP and 100-150 mW heading to the CPU. To be fair, though, the Bay Trail IGP was driving a much higher-resolution display.
In SunSpider, the CPU/GPU split on Clover Trail was 900/350 mW, while Bay Trail's was 1000/475 mW—again, comparable total power use. Of course, Bay Trail finished the SunSpider test in half the time and then dropped back to idle, so it was easily the more power-efficient solution overall.
I think the big takeaway here is that Bay Trail's power consumption habits should make it suitable for eight-hour-plus battery run times in tablets, much like Clover Trail before it. The big change is that you'll be getting substantially higher performance at the same time.
The results we've shown you are admittedly early indicators, but they all seem to point to the same conclusion: that Intel has brought its considerable resources to bear on the tablet SoC market and delivered a best-in-class solution. The Silvermont CPU microarchitecture is a huge step up in per-thread performance, which is just what the Atom has needed for a while now. Bay Trail's graphics are substantially better, too.
The question now is whether Bay Trail can find its way into the hands of consumers in really large numbers, which is the true measure of success for any consumer-focused SoC. For that to happen, Intel doesn't just need to collect lots of design wins in various tablets and convertibles. Bay Trail has to ship inside of systems that are really good, the sort that can be truly popular with consumers. Whether that's more likely to happen with devices based on Android or Windows 8.1 is tough to say. Windows-based convertibles still seem to have tremendous promise, and Bay Trail should allow for the creation of some compelling systems. But Microsoft has barely put a dent in the tablet market so far. Android may be the better opportunity.
At any rate, Intel certainly seems to be doing its part; its tablet SoC offering has made major strides from one generation to the next.
I often post stuff on Twitter using tablets and convertibles.