Venue 8 Pro 32GB - Insane battery drain

The same for me. Unreasonably drains just for doing nothing.

Yesterday I uninstalled all the windows updates to install them again except the KB2883200 (said to be related to this problems). No difference.

After that I uninstalled all the software that could be a potential cause, avast, dell updates, my dell, etc. No difference. I went yesterday night at 60%, and 9 hours after it was at 20% just being there. Wifi must be on (bluetooth off) because if I turn it off, after few minutes it will not turn on and I can only restart the device.

Apart from that, all updates from dell are applied.

the powercfg /sleepstudy tells that for this 40% of drain battery in 8 hours I have the
- Dell Wireless 1538 902.11 a/g/n Adapter working the 100%
- Intel SD Host Controller (\_SB.SDHB) at 99%
- NCSI at 40%
- Intel SD Host Controller (\_SB.SDHA) at 24%
- WNS at 13%

*And this is added to the list of problems
- cannot turn off wifi, I will need to restart the tablet
- extra sensitive touch panel, I don't even need to touch it to type and double-type

A quick update, with WIFI off I have had a 1% battery drain in 2 hours. So definitively it is something with the WIFI drivers.

Same exact problem -- although my DV8P doesn't wait to drain the battery -- as soon as I put it to sleep (or it goes to sleep on its own), the battery drain is like the last part of your graph.

I am about to return my device and tell everyone I know to avoid the tablet because this is INSANE! :emotion-39:

Dell needs to get to the bottom of this AND FIX IT ASAP if they want me to retain any shred of confidence in their product(s).

One poster noticed "normal" drain for several hours and then a precipice on power drain while the device was "visually asleep" (i.e., blank screen)

I appreciate the suggestion - but I'm really waiting on a definitive answer from Dell.

I browsed a few other forums and read a few other threads regarding this issue, and some people said that they were able to reduce battery consumption by disabling the audio drivers.

According to this thread (http://en.community.dell.com/support-forums/mobile-devices/f/4586/t/19532187.aspx), the drivers prevent the device from entering connected-standby mode. Disabling it reduced the power consumption down to <1% over several hours, which is what it should be.

Another person said that they "solved" it by not pressing the sleep button to put the device to sleep, but to just let it go to sleep by itself. I'm a little skeptical about that, but it couldn't hurt to try so I'll do that tonight and see what happens.

I really hope Dell or Microsoft fixes this connected-standby issue. I don't want to return it because I like having a tablet that operates a full version of Windows, but so far, I spent more time doing stuff for this tablet than with it. It's stupid how high-maintenance this tablet it. The battery drained a large amount again last night on standby (27% over 6.5 hours). This time, the tablet still had some power left (62%), but I couldn't wake it up normally. I had to press and hold the power button for 10 seconds and force it to reboot. Absolutely unbelievable.

Putting mine to sleep vs. letting it go to sleep does not make any difference.

Audio states (enabled/muted/normal) make no difference in the battery drain when "asleep"

It is not MY responsibility to know what is or is not preventing my device from entering or not entering "connected standby" -- as it stands, this tablet is TRULY DISAPPOINTING:emotion-39:

The Venue WiFi remains active during sleep, and WILL eventually deplete the battery over 24 ~ 48 hrs (even more rapidly if moved out-of-range from its established WiFi connection). This naughty behavior has been widely reported, and a lot of us are waiting for a firmware fix.

Meanwile my own work-around was to change the Power Button preference on battery power, to shut-down when pressed — from the default sleep when pressed. I left the setting as is, for when it's attached to the charger. Boot-up is extremely rapid, so there's no extra overhead as a result, but I do need to remember to press the button before it falls-asleep on its own!

Two Venue 8 Pro here. Exactly the same experience with both of them.

I suspect that a current-gen micro-SD card would make more sparing use of your battery, although drain is proportional to GB, within the same model card. You didn't reference WiFi & Bluetooth — which I would also expect to be 'big spenders" with your "charge". Did you have them disabled while profiling? (One-half watt per hour still seems rather high, tho I haven't profiled my own V8s for best case discharge.)

Imo, things like this shouldn't/wouldn't be an issue if the Venue BIOS permitted users to specify their own sleep preferences, and — no matter what — would initiate hibernation, as soon as detecting the remaining charge had dropped to a threshold which would still allow re-booting and a quick look-around later on; that's not "rad" tech; lots of older-gen laptops do just that!

Question: are you guys using a micro-SD card with your Venues? I've been using a 2GB card (small, I know) in my Venue since day one, and I think it's part of the reason why my battery might be draining so fast. I have two reasons to believe this:

1. I ran a sleep study on my Venue, and during the connected-standby period in which the battery was losing 806 mW per hour (for a total of 12,090 mWh over 15 hours), the #1 top offender is the "Intel SD Host Controller (\_SB.SDHB) with a % Active Time of 100%. Another session shows 760 mW per hour (5,006 mWh in 6.5 hrs). The Intel SD Host Controller was also the top offender in that session.

2. I ejected the SD card from my device this morning, and so far the connected-standby drain rate dropped to ~430 mW per hour. It's still abnormally high, but it's somewhat better. The drain rate should be ~70 mW per hour.

Basically, from what I observed, the battery loses about 700-800 mW per hour when the SD card was in. When the SD card was out, the rate of drain dropped to about ~430 mW per hour.

What do you guys think?

I have added a 64GB SanDisk uSD card to both of my 2 Venue 8 Pros and I also noticed that the Intel controller frequently is in a top position in the powercfc generated list of "problematic" devices (as is the Wi-Fi). 

No SD card in my case ...

I bit the bullet and reset my device to factory settings (after having updated the various bios images) and "so far" (24 hours) the CS is only drawing about 75mwh. I won't know for a few more days if I'm out of the woods yet.

Yes, I should've mentioned that WI-FI and Bluetooth were switched off for the connected-standby sessions that I looked at. I've been doing a lot of trial-and-error to see if I can find out what's draining the battery the most, and I try to keep everything the same. So far, taking out the SD has made the greatest impact.

I can't say for sure if there really is a problem with the SD card driver or if it's just a coincidence.

In any case, I just finished factory-restoring the Venue. This time I'm not going to update anything and see if that helps. I'll wait for Microsoft to roll out a service pack or something.

So, after having uninstalled and installed the WIFI drivers (necessary to uninstall first), and following that after installing all the updates from windows, I have correct battery drain, i.e. with WIFI I have less than 10% overnight.

I haven't check whether I can turn off and on WIFI (which has never worked if I leave few minutes in between). But other than that, I am happy.

- I have a SD card class 4 of 32 Gb connected, but the SD driver has stopped working at 100% after re-installing the WIFI drivers.

- I have the audio working (some weeks ago I disabled and enabled it to make it dissappear from the "requests" of the system. Don't know if that is helping me know, but I doubt it. So far I give all the credit to re-installing the WIFI drivers.

Bottom-line message, it is obvious that this tablet is not prepared for standard users. Out of the box it is not working at all, and now I do not dare touching anything to avoid possible risks of having problems again. Obviously, the user experience is extremely worse than what you can get with an android / apple tablet. And this is a shame.