I’ll give you the poison pill straight away: Windows 10 cannot and will not be as Power-efficient compared to Windows 8! Not on an x86 device. On ARM, it’s another ball game. This is why MS is having issues with ARM devices and Desktop for Windows 10 generally.

See, the reason here is simple, since the rejection of Windows 8 platform by the masses who doesn’t understand the OS, Microsoft’s hand has been forced to abandon all the progress made on re-writing Windows from the ground up for a great mobile experience, and concentrate on the Keyboard & Mouse world to make Windows 10 acceptable to Desktop huggers and the Enterprise in general.

This means dumbing down the progress made in Windows 8 timeframe and bringing up Windows 7 UX to the next century. For me I don’t consider Windows 10 the next evolution of Windows 8, but an evolution of Windows 7 with a nod to Tablet/Mobile users with the Continuum technology in it. Windows 10 is Keyboard/Mouse first and Touch second.

Which brings me to the topic at hand. Because of Desktop and UX technology of Windows 10 that mimics Win7 UX, you get to keep lots of windows open. Each opened Window is an active resource in Win10, which means active drain on the battery.

Compare this to Windows 8 which is a single focus OS. The currently opened window in Win8 is the only window tasking the CPU, all other “invisible” windows are put on ice. Sleeping if you get what I mean. The only type of windows that tasks the system while not in focus are those that you allow to run in the background specifically. And guys, this is why you get the warning when you have too many background task Apps in Windows 8 and 10. Like the max number of Apps that can put messages on the Locked screen for example.

On a Desktop device that is continually powered, you will not notice this issue, but if you’re on any x86 mobile device with Desktop, you will have this problem if you do not activate the Tablet mode. The only way to avoid battery wastage then is to minimize every windows you’re not using while on a mobile device with tablet mode not activated. When windows are minimized, they are put to sleep like in Windows 8.

As you can in the title Picture above (click to see larger), I have taken my favorite TV app TrackSeries as an example. This modern app makes full use WPF with lots of eye-candy and animated thingymagic all over the place. As you can see above, even while it is out of focus, it is still draining the CPU at 13.5%. (Of course this is a snapshot, it varies continuously.)

Now take a look after the App was minimized:

The system puts the app to sleep after a few seconds. You will notice some apps that are still active even after they’re minimized while not been set as background apps. These are apps like twitter and mail clients that are making use of connected standby feature of Windows 8/10 that is designed to keep your info-stream up to date even when your app is iced.

So to save battery in Windows 10 x86 (i.e. screen >= 8″) devices, either activate Tablet mode (which essentially switches you to Win8 single-focus mode) or actively minimize all windows you’re not using.

Final note: Please realize this post only relates to Windows Store Apps or Modern Apps like Microsoft like to call them. Those of us puritans call them Metro Apps for nostalgia sake. I am not talking of old Win32 desktop Apps, which will continue to drain battery whether you have them minimized or not. (That is why we developed Metro Apps technology in the first place!). For example, IE11 you see here above is Win32 App.

So now you know. If the same device that was reaching 8 to 10hrs with Windows 8 is not reaching it anymore with Windows 10, you might want to watch how you’re using Windows 10 regarding windowing. For me, I always have the TaskMan icon next to the clock to keep an eye on my CPU=battery drain while I am in mobile mode.

Have you noticed this yourself, or do you disagree with me? Comment below and let’s have intelligent discussion about this.