Battery drain while suspended


#61

@twinkybot

Just for “our” statistics: Can you estimate how long your Librem can stay suspended until a fully loaded battery is empty? And which Librem do you have? And which OS are you using?


#62

Short update:

After having changed the RAM bar from Crucial to Samsung one year ago on my Librem 13 v2 (see earlier post here) the battery could stay about four days in suspend mode until it was empty.

I have updated my firmware now to Version: 4.9-7 (built May 16 2019) and the battery supports five days in suspend mode now. I am using Ubuntu 18.04 with the latest HWE stack (kernel etc.) so it may also have improved due to better Ubuntu support.

I have not yet used any powertop settings to improve the battery lifetime…


#63

I have a Librem 13 v3 with the Crucial 16gb RAM. I am running the latest PureOS. I can get 4 days of standby on it. This is after I’ve used it some, so not even at a full battery. I’ve noticed about 14-22~% battery drain per 24 hours.

That is fine for me.

Personally a better solution to swapping RAM and tweaking power settings (although important) would be to get hibernation working and not worry about how much power you are sucking on while in standby.

It is a pain to setup on the Librem because of Luks and there being no clear guide to setting it up, but that is the best solution, IMHO.


#64

As stated above, my Laptop is a Dell XPS 13.


#65

I just changed the Crucial 16GB RAM module CT16G4SFD824A.C16FHD1 which came with Librem 13v4 and changed it for 16GB module from HyperX.

It works and after brief test it seems it solved the high drain issue. I measure 0.00 A on the DC power supply while suspended with fully charged battery. Not like before:

I will suspend it unplugged over night and will see.


#66

Please do. Interested to hear it. I think there has to be some power used or the ram would not retain the data. :+1:


#67

My limited understanding is that it has to do with sleep states. I have a D3LL XPS 13 and the drain happens in w1n10 (I have been told is due to the limiting of how the device is allowed to sleep… AKA less options for “sleep states”) I have not found a workaround. Like it is baked into the board and chips… so we can never truly have the device off… not unlike some cellphones… “for our convenience” LOL
(Would love to be wrong, but seems like built in obsolescence aka shorter product lifespan)


#68

After 10 hours suspended and unplugged the battery status was 94%. So it is much better than before the RAM change.


#69

Thank you! Yes, a power drain of some type MUST be present if the device is sleeping / in standby mode. RAM must have power to retain data.

Is that 94% from a full battery?

If so I am getting similar results with the stock RAM I have in my L13v3 now.


#70

Yes from full battery. With my original RAM it was way worse (like 50%) over night.


#71

Ok then it sounds like you had a faulty stock RAM chip. 50% over night is not normal in anyway.

Glad you got it all working great. The Librem 13 is great!