Battery Drain with 2016 MBP and OWC Thunderbolt 2 Dock

[ugahairydawgs]

Is anyone else using the new 2016 MBP with OWC TB 2 dock connected with the TB 2>3 adapter? I've been having a terrible time with battery life using mine to connect to an external monitor, along with several other peripherals. Right now the only things I have open are Safari, Mail, Fantastical, OmniFocus, Messages, Slack and Activity Monitor. I hooked up around 45 minutes ago and have gone from 80% on the battery to 50. I'm getting about 2 hours total, but only when connected to the dock (this happens on both my home and office setups). When I'm not on the dock I'm getting a good 7-8 hours of battery life.

Anyone else using a similar setup having issues like this? I'm assuming something is triggering the discrete GPU, but I don't understand why. I used the same dock, monitor, peripherals with my 2013 MBP for a year or so and never had any issues like this.

 

[ManuCH]

The external monitor triggers dGPU.

I'm curious: why can't you connect the power supply when you're at your desk with a dock?

 

[ugahairydawgs]

The external monitor triggers dGPU.

I'm curious: why can't you connect the power supply when you're at your desk with a dock?

I can (and do). I just don't want to leave it connected all the time and end up killing the (glued in) battery too early in it's life.

Any idea why the external monitor would need to automatically trigger the dGPU? The integrated chip on the 2013 model was more than enough to power these monitors before, so I'm just curious as to why this would be happening now. If I were running 4k or 5k screens that would make sense, just wasn't expecting this to be such a drain on the battery.

 

[thats all folks]

I can (and do). I just don't want to leave it connected all the time and end up killing the (glued in) battery too early in it's life.

how would using the power supply kill the battery?

 

[ManuCH]

I can (and do). I just don't want to leave it connected all the time and end up killing the (glued in) battery too early in it's life.

Any idea why the external monitor would need to automatically trigger the dGPU? The integrated chip on the 2013 model was more than enough to power these monitors before, so I'm just curious as to why this would be happening now. If I were running 4k or 5k screens that would make sense, just wasn't expecting this to be such a drain on the battery.

AFAIK leaving it connected doesn't kill the battery. OTOH, charging and discharging all the time shortens battery life. It's OK to leave it always connected - I make it a habit to discharge the battery fully once a month or so. It's fine.

Anyway, if a MacBook has a dGPU, I think it must be used for external monitors as the iGPU is not capable or not connected to the external connectors. But I don't have solid proof of that, maybe someone else can chime in.

 

[ugahairydawgs]

how would using the power supply kill the battery?

Maintenance docs on lithium ion batteries have always said that for their long term health its best to keep the electrons in them moving (charge and discharge).

 

[ManuCH]

Maintenance docs on lithium ion batteries have always said that for their long term health its best to keep the electrons in them moving (charge and discharge).

I still have 2011 MBP somewhere at work that has been connected to the power supply about 90% of the time. Hardly lost any battery capacity, no issues whatsoever.

 

[poorcody]

Maintenance docs on lithium ion batteries have always said that for their long term health its best to keep the electrons in them moving (charge and discharge).

In theory, but batteries also have a fixed number of charge/discharge cycles... if you cycle it everyday, you are going to significantly lower your battery's performance. On my 2013 MacBoor Air, my battery lasts as long as it did on day 1 because I had it plugged in 80-90% of the time.