rMBP Odd Battery Life

[kmanmx]

Hello,

Had my rMBP for about 3 days now. First 2 days, battery life was exactley as expected. But last night I totally powered the MBP off, and since starting it this morning battery has been decreasing faster than I would expect.

For example, right now I am just browsing the web and download a 700Mb file from the net which will take 30minutes. I'm on 25% battery life, and it says I have 40 minutes left ? If you extrapolate this information, you can deduce at this rate of discharge a 100% full charge would last about 3.5 hours. That seems like half of what it should be ?

The apps I have open are Finder, App Store, Google, Chrome Canary and that is all - at least to my knowledge looking at the dock bar (It's my first time using OS X so I am not massively knowledgeable). My screen brightness is at 50%, key backlighting off, nothing plugged into USB, and no music playing.

Any ideas ?

 

[stevelam]

Constant downloading via wifi will of course drain the battery.

 

[kmanmx]

Constant downloading via wifi will of course drain the battery.

I know WiFi downloading has some effect, but could it really be the cause of halfing the normal 6 or 7 hour browsing life time ? Its only downloading at 300KB/s.

I also notice sometimes the rear of the rMBP can get very hot when browsing, it will then cool down.. heat back up etc. I am assuming this is from the discrete graphics chip being turned on and off - as cpu usage is pretty much constant. If so, it seems to turn on unnecessarily sometimes, and can't help towards battery life.

 

[ohbrilliance]

osxdaily.com had similar findings with heavy wifi usage on the MBA.
http://osxdaily.com/2012/06/26/battery-life-on-macbook-air-2012-is-better-than-advertised/

They don't have an explanation. stevelam, why do you say it will 'of course drain the battery'?

 

[Dangerous Theory]

My first question would be did you install Samsung kies software? If so, culprit found.

 

[sweetbrat]

Keep in mind that the estimated time remaining is just that...an estimate. It's a snapshot based on exactly what you're doing with the computer at that time. Once it stops downloading, do you see the estimated time remaining jump back up again?

 

[gigapocket1]

I downloaded gfxcardstatus.. Forces my computer to use the integrated graphic card when running on battery.. Greatly improved battery life on my machine.. Well made it more consistent

 

[kmanmx]

Thanks everyone. The download finished and estimated time increased by 20%, forcing integrated GPU helped too,