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Zen Desk Pro

macrumors member
Original poster
Aug 18, 2015
62
9
Chicago, Illinois
Hey guys,

About a month ago, I purchased a brand new Mid 2014 rMBP. It's a 15 inch with 512 GB storage on it.

The official specs page on Apple's website claims up to 8 hours of wireless web browsing. I've been doing almost nothing but web browsing since I got it, however, I'm not getting anywhere near 8 hours of wireless battery life off of the charger.

Not even close to 6. What could be the reason?


Now, to shed a little bit more light into my set up:

My brightness is at about 70% at all times (but set to automatically adjust)

Keyboard backlight is off unless I choose to turn it on manually (almost never)

I'm also usually connected to a Thunderbolt display (and use my Macbook as a "second" monitor on the side (since I choose not to leave it on the charger 24/7).



Could this explain my dramatic reduction in battery life? Does docking to the Thunderbolt display hog battery? Is 70% brightness too high to expect even 5, or 6 hours of casual web browsing battery life?

Help me understand!




Thanks.
 
I would say the biggest power draw is the connection to the Thunderbolt display and try 60% brightness. Some other things that draw power are activities that use Flash and using Chrome for a browser.
 
I would say the biggest power draw is the connection to the Thunderbolt display and try 60% brightness. Some other things that draw power are activities that use Flash and using Chrome for a browser.
That's a really good point. I guess I'll have to try to test the battery life again, but instead off of the Thunderbolt display. I had no idea it could be such a battery hog, though.


Thanks for your answer.
 
Driving a second display will consume a significant amount of power. Why aren't you plugged in when connected to the display?

Otherwise, open the Activity Monitor and go to the Energy tab to get a handle on what processes are using significant power. Any reading in the single digits is worth looking at. Anything ~50 or above is a significant power draw.
 
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Driving a second display will consume a significant amount of power. Why aren't you plugged in when connected to the display?

Otherwise, open the Activity Monitor and go to the Energy tab to get a handle on what processes are using significant power. Any reading in the single digits is worth looking at. Anything ~50 or above is a significant power draw.
Because that can't be good for the battery, can it? Constantly being connected to the charger? Even if you're not necassarily "away" with your notebook.
 
When Apple says a laptop can a certain amount of battery usage, they are using it under very strict settings. The display is turned down to a certain brightness, there is nothing attached to any of the ports and they just set the computer to do one activity during the entire time.

I turn my brightness down to below half, turn off the keyboard lights and just more or less use mine for internet, twitter and a few other related apps. I van about six hours this way on my 2015 15" i7 quad core MBP.
 
Because that can't be good for the battery, can it? Constantly being connected to the charger? Even if you're not necassarily "away" with your notebook.

Much better than constantly draining the battery and putting cycles on it, yes leave it plugged in unless you are using it as a laptop it will help preserve your battery. Bad battery management firmware in the past has certainly meant that batteries could over charge etc but that hasn't been the case for about a decade.

Read this link for all modern apple battery information.

https://forums.macrumors.com/thread...ry-every-day-good-or-bad.914068/#post-9875442
 
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The external display switches to the dGPU by default, this is why the battery consumption is heavy. If you want to "exercise" the battery just run it down by 20% once or twice a month, right now you are consuming battery cycles for no purpose.

Q-6
 
The external display switches to the dGPU by default, this is why the battery consumption is heavy. If you want to "exercise" the battery just run it down by 20% once or twice a month, right now you are consuming battery cycles for no purpose.

Q-6

This. The dGPU can use up to another 35W of power. If it's at a desk I'd run it on mains power.

Also, are you using Chrome?
 
Thanks, guys.

I guess I'll keep it on the charger when at the desk. Plus, it makes it nicer because I can use it in clamshell mode (I'm sure that me using both the external display AND the laptop open consumes even more battery. Nonetheless. Four hours with that set up, now that I think about it, is kind of impressive.

I was worried because I used my old PC laptop as basically a desktop and had it plugged in all the time. The machine could barely survive 2/3 hours off of the charger - and I thought that this might be due to how often it was running on the charger.

I use Safari for the sole reason of not having to deal with a fan running, unreasonable amounts of RAM and memory being used up, and preventing my computer from overheating (because that can't be good for the machine in the long run). I've sacrificed a lot by switching over, but it's been worth it. I don't know for sure yet, though -- I might go back to Chrome.
 
Thanks, guys.

I guess I'll keep it on the charger when at the desk. Plus, it makes it nicer because I can use it in clamshell mode (I'm sure that me using both the external display AND the laptop open consumes even more battery. Nonetheless. Four hours with that set up, now that I think about it, is kind of impressive.

I was worried because I used my old PC laptop as basically a desktop and had it plugged in all the time. The machine could barely survive 2/3 hours off of the charger - and I thought that this might be due to how often it was running on the charger.

I use Safari for the sole reason of not having to deal with a fan running, unreasonable amounts of RAM and memory being used up, and preventing my computer from overheating (because that can't be good for the machine in the long run). I've sacrificed a lot by switching over, but it's been worth it. I don't know for sure yet, though -- I might go back to Chrome.

Try Chrome Canary it`s more optimised for OS X, should help to keep the fans from spooling up so much.

Q-6
 
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Because that can't be good for the battery, can it? Constantly being connected to the charger? Even if you're not necassarily "away" with your notebook.
This battery myth is outdated by about 10 years and needs to die a quick death.

Your LiPo battery doesn't care one bit how you treat it. Plug it in whenever you please, keep it plugged in for months on end if you like, you're not going to harm it. The power supply, as its name implies, is just a supply. The battery is the one that decides if it needs juice or not, it cannot overcharge or any of that nonsense. No matter what you do to it, it'll die about 5 years down the road, from old age. Avoid temperature extremes ( and I do mean extremes, like sticking it in your freezer or having it sit on a car dashboard out in the sun on a 30C+ day), and all is well.

FWIW, there are different qualitites when it comes to batteries. I'm guessing your older Windows computer had a poorly designed one.
 
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