I’m inclined to believe it’s more of a hardware/driver issue, in fact, I’m almost certain of it.
Why am I so certain? Because my Samsung Ativ SPC, which not only has a touch interface and windows 8 running but also the Samsung touch pen tech to boot is apparently capable of running for over 10 hours, here’s the Anandtech benchmark (the same one used here):
http://www.anandtech.com/show/6827/samsung-ativ-smart-pc-revisiting-clover-trail-convertibles/5
Found it: http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.html
“In order to prevent active attacks, device drivers are required to poll the underlying hardware every 30ms for digital outputs and every 150 ms for analog ones to ensure that everything appears kosher. This means that even with nothing else happening in the system, a mass of assorted drivers has to wake up thirty times a second just to ensure that… nothing continues to happen”
So there you go, your video and audio drivers have to poll the hardware repeatedly, which takes all of the CPU, video, and audio hardware out of low-power state when they could otherwise be idle.
As far as I know, this remains the spec for drivers, and does partially explain why Windows would use more power at idle than other operating systems.
In the top showed absolutelly different tests for Surface and Macbook Air.
Look at this test http://images.anandtech.com/graphs/graph7417/59018.png
OS X powered Haswell Macbooks eats 30% more power than Windows 8 powered Sony. What is more Sony has 1080p IPS touch display and Macbooks has low-res TN crap.
Apple Bootcamp drivers have always been shit. Perhaps intentionally.
So the whole post is a groundless fantasy.
The only fact is what Surface Pro 2 shows bad results in sprint Anand’s test. Anand hurried to plane )
PC browsers are alot better than Mobile OS browsers for me though, so my Android and Windows machines go hand in hand
Thank you for the link Gordon.
I do remain skeptical, however, of the content. I don’t know that it’s wrong, but its last update is over six years ago, and there seems to be a lack of supporting evidence.
It would be easy enough to prove, if true. Somebody could find the current requirements, or could record an xperf trace that shows drivers doing this. Without some sort of recent confirmation I remain skeptical.
But, next time I’m looking at an xperf trace I’ll watch for signs of this behavior. If I find anything interesting I’ll be sure to blog about it.
Aionescu wrote: “It is utterly unfair to compare Windows on a Mac laptop. Regular Windows-compatible (OEM/designed-for/Logo’ed) machines have something called “ACPI Tables””
That would be more compelling if Windows’ battery life on a Mac laptop was not pretty much the same as Windows’ battery life on a non-Mac laptop with similar specs. And if a similar differential wasn’t seen on non-Apple Hackintoshes.
Also, Apple may well provide the appropriate ACPI stuff for Windows among the Bootcamp Windows drivers for Apple hardware.
Do you have same display brightness in osx and windows 7? I was working on a mac book pro with win 7 and had the same problem . Minimizing the brightness in windows did the trick. Btw it seems mac osx is optimized to work with a dim screen. Same brightness level does not work well with windows.
@Randomascii.wordpress.com
“Comparing Windows and OS X on the same hardware seems like the ideal comparison since it reduces the number of variables, but it actually turns out to be bad science, I believe. Apple supplies the Windows drivers for their hardware and they have no incentive to provide best-of-breed Windows drivers for their hardware. In order to sabotage the Windows results they merely have to not spend a lot of effort on optimizing their Windows drivers.”
This sounds plausible and stuff, but it’s actually completely not true.
Intel macs are not ferraris, and they aren’t built out of tons of fancy bespoke components. If you look at what the windows boot camp driver partition actually contains it’s just the totally standard(and usually several versions behind current) Nvidia/amd graphics drivers, intel chipset drivers that were standard at the time for that CPU, normal atheros wireless drivers, bluetooth drivers, etc. Stuff like the sound driver will have it’s fancy crappy system tray amp dumped off but still be the normal >INSERTSOUNDCHIPSETMANUFACTURER drivers. All that stuff is exactly the same as you’d get on a comparable hp probook or lenovo, etc.
The only special apple stuff is mustard on the hotdog like the silly little bootcamp tray applet that does things like give you an approximation of the OSX volume changing overlay, and a similar hotkey hook driver to the one that lenovo, dell, hp, and everyone else use.
There’s no “unoptimized custom version” of the intel chipset drivers or really anything going on here. You can really see the flipside of this in how many systems there are that OSX will boot on 90% or higher completely unchanged. Check out this list if you’re curious or want a reference for what i’m saying:
http://www.macbreaker.com/2012/09/best-hackintosh-laptops-2012-mountain-lion.html
Oh and by the way, for this reason there used to be forum threads out there i don’t feel like digging out right now that were guides on how to get all the hardware in your intel mac working on XP or vista in the early days when it wasn’t totally supported(and also on the 32 bit early macbook pros/imacs that they didn’t ever support well), or 64 bit windows 7 on the systems that didn’t support it by default with bootcamp. People had easily compiled lists of where to go grab compatible drivers from the manufacturers sites. Apple isn’t making custom bluetooth chips or anything(…yet).
So yea, as a closing note to tie up my argument here… There isn’t any legitimate reason that the battery life should be this different on a macbook because of drivers. The driver argument just doesn’t float as “bad science”. They’re the same drivers everyone else uses, running on most of the same hardware when it comes to stuff that’s at an actual level to have drivers in windows. There are no mysterious deep system level drivers getting popped in by the bootcamp driver installer app.
A compelling argument if someone could back it up would be that there’s some complicated power management modes in the PMU/battery controller that only OSX gets to touch, much like how some of the switchable graphics macbook pros can only use the high-power card on windows. If that was the case though, then i still don’t see how we should be seeing such a stark difference on the integrated graphics only systems though. This gap existed even in the 1st gen plastic macbook days with the gma950.
Might be interesting to compare with Windows on Parallels or VMWare… Does reduce Mac running time, but maybe still beats Bootcamp?
How about taking a Bay Trail tablet that runs Windows and putting a custom Android ROM on it. That would be an interesting comparison.
@Gordon Messmer
"Found it: <a href=“http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.html”">http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.html"
This article is also highly dubious:
http://www.zdnet.com/blog/ou/gutmann-vista-drm-paper-uses-shoddy-web-forums-as-source/723
http://www.zdnet.com/blog/bott/everything-youve-read-about-vista-drm-is-wrong-part-1/299
and parts of discussion here:
https://www.schneier.com/blog/archives/2006/12/a_cost_analysis.html
and dozens of discussions about this.
Thanks for this great comparison. I’m in the process of deciding upon a tablet AND this info is perfect!
Why include the NVIDIA Shield and the Google Nexus 7 in the first graph?
Comparing a 5 inch screen and a 7 inch screen to devices with 10+ inch screens is going to be an unfair comparison. Of course they win.
Take those 2 products out and the graph makes more sense.
@Tomislav Tustonic
I’m not going to assert that all of the claims in that paper are true, but I’ve read through all of your links. There’s almost no questioning or debunking in Schneier’s blog, and some of the other blogs “debunking” the paper are very clearly incorrect. Some of those are contradicted by Microsofts own answer to Guttman’s paper, which includes:
http://blogs.windows.com/windows/archive/b/windowsvista/archive/2007/01/20/windows-vista-content-protection-twenty-questions-and-answers.aspx
"Will Windows Vista content protection features increase CPU resource consumption?
Yes"
Guttman may be wrong about a number of his claims, but I’m not sure zdnet bloggers are really much more accurate.
Integration + 35 years. That’s the answer.
Software optimization by itself isn’t enough. What do you optimize for? At any given time Apple might have a handful of iOS hardware products and another handful of MacBooks, but Microsoft has hundreds. This is where vertical integration comes into play. Controlling the hardware and the software allows you to target your software efforts to a particular combination of hardware, and develop your hardware to take advantage of software advancements.
You say that drivers are partially to blame? Sure, I agree. But why do you need drivers for five thousand hardware devices? Again, this is the joy of an open platform where anything goes, versus a tightly integrated product with hardware and software developed in concert, backed by a third century of experience perfecting just that.
Integration + 35 years. That’s the answer.
Maybe Windows is simply using more power both when idle and when used for any activity.
Obviously, Apple does a much better job in handling the power needs of a computer.
I’d like to know if those tests were done at the same brightness (equal nits) or same setting (max/X%/min). I’d prefer them to be done at equal nits to get true comparisons.
“We’re at a loss to understand why Windows’ terrible – and worsening! – idle battery life performance isn’t the source of far more industry outrage.”
Because pretty much everyone who cares about that sort of thing switched to Macs and iOS devices years ago. The people are still using Windows and not clueless users or corporate drones – in other words those who know better – mostly fall in two categories: hardcore gamers, who tend to use desktop machines and don’t care about battery life, or techies who make their living as Windows coders or SysAdmins and don’t want to rock the boat.
For the rest - why be outraged? Why waste your energy? Just buy an Apple device the next time you need to upgrade.
This happens because Apple is the only mobile company out there right now who isn’t doggedly trying to shoehorn the entire desktop computing experience into their mobile devices.
You should have a look at the new OS X 10.9 Mavericks! Ars technica reports further significant improvements with an increase in battery life of roughly 25-30%
see http://arstechnica.com/apple/2013/10/os-x-10-9/18/#battery-benchmarks
Really impressive - is anyone aware of best practices for energy efficient coding?
