Surface Pro 3 short battery life

No, when they had said "up to 9 hours battery life", they where talking in general.  All three of these tablets have the exact same battery packs but each processor (i3, i5, and i7) uses electricity different because of the number of cores.

I have worked with the laptop versions of these processors and they definitely get a different battery life when comparing the CPUs.  The i3 was the only one I didn't work with until I got my Pro 3.

The i5 has TurboBoost built into it and there is no control for it.  It only kicks in for a few seconds when needed and the user usually never knows it kicked in.  It is the only CPU in the series that has it but it uses power more than normal when it does operate.  The i7 definitely uses more power than the previous two.  You cannot get that much processing power without using electricity.

So, when you have three tablets built exactly alike to include the same RAM memory type and the only difference is the CPU, you are going to see a difference.  That is recognized by even the regular PC makers (HP, Dell, etc.).

If these machines had the proper engineering done on them, you would get 10+ hours from them with full use.  It would require different battery packs per CPU type but those exist or can be built.  LG Electronics makes the battery packs for the Pro 3 series and are custom built just for them.  The big issue is that you have to use the right parts to build the machine with.

With my i3 model, it gets 6.5 hours with normal use just as a normal person would use one and I consider that good.  You may have noticed throughout the forum that there is little or no mention of the i3 model.  This particular one may not have any problems at all compared to the other two.

Getting longer battery life from a Windows 8 system has already been proven.  I mentioned the Asus T100 with the ATOM processor; it gets 11 hours per charge.  That is going full bore and full use with it.  BUT, it has a real Broadcom network adapter.  Not this 'flakey Jake" Marvell AVASTAR series.

I have been seeing my battery drain overnight lately as well. E.g. I will have 50-60% battery left and I click on Sleep before going to bed myself and by morning the battery is basically dead and I have to plug it back in before it will start up.

I don't buy 5 hours is to be expected. That is NOT what Microsoft is saying. They are saying up to 9 hours for ALL processors. The only disclaimer they have is: Testing consisted of full battery discharge while Internet browsing over WiFi. Internet browsing was tested browsing 25 popular web pages. All settings were default except: Wi Fi was associated with a network, Auto-Brightness disabled, and Bluetooth Radio was turned off. 

Corporate Vice President Panos Panay and members of the Surface team acknowledged that despite the difference in processors, the battery performance will be roughly the same across all the new Surface Pro 3 models.

My usage is similar to their tests with the exception of email, Word and PowerPoint...for that I should not expect to see 55% decrease in battery life. Especially when compared to a similarly equipped MacBook Air.

So, either they are flat out lying or something is terribly wrong with the device or the software...I suspect the software as mentioned above, similar hardware on an MBA is 10+ hours.

Yea, now if you live on a web site, that eats a lot of juice.  There is no public WiFi where I am at and was running a "field test" where the tablet is off-line.  Since these tablets are portable, a field test is what you do and you connect if it is available or off-line when it is not.

If you are not on the Internet, you will see your battery life go up.  Myself, I was using Office 365, Xara Photo editing, Gimp, InkScape, and some rounds with Microsoft Solitaire to include Music and Videos.

Now, if I was in a connected environment and fired up the web browser, that battery life will go down.  There are too many elements on a web site these days and those elements will suck up the juice like crazy.  Microsoft's web site is actually minimal in elements compared to news web sites such as NBC, ABC, and CBS.

But, if this tablet was LTE, that would be a different picture and 4 hours would probably be the maximum.  That would be with the i3 model.

No, I left the brightness alone.  In fact, the only thing I did was shut off sleep mode when on A/C.  Now, this is the i3 model and the CPU uses a lot less resources than the i5 and i7.

The battery will click down when doing a lot of web browsing or listening to music.  Did not pay much attention to video playback but did watch one movie and one TV show and the battery level barely moved.

It is possible that I may have a rare machine that has no defects or that the i3 models have no issues compared to the i5 and i7 models.

As for 8 or 9 hours of use; I think that was from one test bench model (i3) with nothing attached to it and all they did was turn it on and clocked it.  Not connected to the Internet either.

Only an ATOM processor could be productive and provide a 9 hour battery life.  I have the Asus T100 that gets 11 hours and I tested that 4 times and it actually does it.

I would say that it would be normal for the i3 to get about 6 to 6.5 hours, i5 about 5 hours, and the i7 about 4 to 4.5 hours with normal use and being conservative.

Now, if you shut the brightness down too much, it becomes not useable in a normal sense.  It is actually not worth it and the light panel is LCD and uses very little power.

Now, I did not detach the keyboard/cover and tested the duration of the battery that way.  I probably could get more by doing that.  I also don't use OneNote and barely use the pen at all.

My email is POP3 so it pings the server in milliseconds and should not even register power usage.

So, if I did go more conservative, I could probably stretch the power consumption to 7 to 7.5 hours (possibly).

The type of program that you are running and the way it was coded is very important, just open Microsoft, don't play, leave it idle, turn off everything else you can and you will get 4 hours of battery at most.

And for the record, I can get more than 6 hours of battery in my i5 as long as I stay away from Google Hangouts something that I can't. So my battery life since I got the SP3 is reflecting almost 6 hours.

No, I left the brightness alone.  In fact, the only thing I did was shut off sleep mode when on A/C.  Now, this is the i3 model and the CPU uses a lot less resources than the i5 and i7.

The battery will click down when doing a lot of web browsing or listening to music.  Did not pay much attention to video playback but did watch one movie and one TV show and the battery level barely moved.

It is possible that I may have a rare machine that has no defects or that the i3 models have no issues compared to the i5 and i7 models.

As for 8 or 9 hours of use; I think that was from one test bench model (i3) with nothing attached to it and all they did was turn it on and clocked it.  Not connected to the Internet either.

Only an ATOM processor could be productive and provide a 9 hour battery life.  I have the Asus T100 that gets 11 hours and I tested that 4 times and it actually does it.

I would say that it would be normal for the i3 to get about 6 to 6.5 hours, i5 about 5 hours, and the i7 about 4 to 4.5 hours with normal use and being conservative.

Now, if you shut the brightness down too much, it becomes not useable in a normal sense.  It is actually not worth it and the light panel is LCD and uses very little power.

Now, I did not detach the keyboard/cover and tested the duration of the battery that way.  I probably could get more by doing that.  I also don't use OneNote and barely use the pen at all.

My email is POP3 so it pings the server in milliseconds and should not even register power usage.

So, if I did go more conservative, I could probably stretch the power consumption to 7 to 7.5 hours (possibly).

The type of program that you are running and the way it was coded is very important, just open Microsoft, don't play, leave it idle, turn off everything else you can and you will get 4 hours of battery at most.