Might it be that the Win7/Vista drivers for the MBA are worse that the OSX drivers?
We see the comparisons:
Surface <-> iPad, OSX MBA <-> Win7/Vista MBA
Surface has different architecture than the iPad, so the battery difference is easily explained, and maybe driver support is just less than stellar, meaning HW isn't as efficient and/or doesn't scale back quickly enough?
I had an Asus laptop some years ago that would last 3 hours under Vista, and would be dead in the water in 1 hour under Ubuntu. I think it was either GPU or CPU scaling or both that wasn't supported in the linux drivers I was using
>I had a brief Twitter conversation with Anand Shimpi of Anandtech about this, and he was as perplexed as I was. Nobody could explain the technical basis for this vast difference in idle power management on the same hardware. None of the PC vendors he spoke to could justify it, or produce a Windows box that managed similar battery life to OS X. And that battery life gap is worse today – even when using Microsoft's own hardware, designed in Microsoft's labs, running Microsoft's latest operating system released this week. Microsoft can no longer hand wave this vast difference away based on vague references to "poorly optimized third party drivers".
We see the comparisons: Surface <-> iPad, OSX MBA <-> Win7/Vista MBA
Surface has different architecture than the iPad, so the battery difference is easily explained, and maybe driver support is just less than stellar, meaning HW isn't as efficient and/or doesn't scale back quickly enough?
I had an Asus laptop some years ago that would last 3 hours under Vista, and would be dead in the water in 1 hour under Ubuntu. I think it was either GPU or CPU scaling or both that wasn't supported in the linux drivers I was using