rMBP 15 - Bad battery?

Discussion in 'MacBook Pro' started by Soundcheck, Nov 4, 2012.

  1. Soundcheck macrumors newbie

    Oct 27, 2012
    I've had my Rmbp 15 for like 3-4 days and i think my battery is bad.
    When battery is 100% it says it will last for 4:15 mins and i have turned down brightness to 40% and the only thing im using is a web browser with 2 tabs.

    Bluetooth is off.
    Keyboard light is off.

    My main concern is that it will only last 2h when im watching a movie or sum.
    What do you think?

    Is this normal or should i take it to inspection?

    How long does your rmbp last, and what are you doing ?
  2. GGJstudios macrumors Westmere


    May 16, 2008
    First, the time remaining is only an estimate, and varies from minute to minute, based on the current power demands at any given point in time. A truer indicator is how long the battery actually lasts until your Mac shuts down.

    There are many factors that impact your battery life. See the BATTERY LIFE FROM A CHARGE section of the following link for details, including tips on how to maximize your battery life.

    The link below should answer most, if not all, of your battery/charging questions. If you haven't already done so, I highly recommend you take the time to read it.
  3. maratus macrumors 6502a


    Jun 12, 2009
    It may not be related to your particular issue, but for some reason currently the system battery runtime estimation in Mountain Lion is no longer accurate and consistently shows less and updates very slowly.

    I would suggest you to install iStat Menus which proved to be more accurate for me especially in low power conditions.

    And of course double check all of your and system background processes. The trick here is that 2 years ago all mobile processors in MBPs (Core 2 Duo) had only two cores and now hyper-threading, so that means only 2 threads. If any process glitches and loads one thread up to 100% you'll immediately notice that by significant reduction in battery life and fans going off. Now we have 4 cores and 8 threads, so that one buggy process wouldn't have such a significant impact. You'll end up with 3.5-4.5h of battery life out of the full charge in that case. That's why you should be very careful and check out activity monitor.
  4. maratus macrumors 6502a


    Jun 12, 2009
    By the way, under your specified conditions my RMBP lasts 7.5h or more (light browsing, wifi on, 35-45% brightness etc.)

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