Scaled Retina Resolution: Battery Drain

Discussion in 'MacBook Pro' started by -BigMac-, Apr 3, 2014.

  1. -BigMac- Suspended

    -BigMac-

    Joined:
    Apr 15, 2011
    #1
    Hi Guys.

    I was wondering how much extra battery drain/cpu usage there is when using scaled retina resolution as opposed to 'best for' retina.

    I have noticed some increased battery usage since changing to the '1920x1200' scale. Maybe this is just my mind playing tricks.

    Anyone shed some light on this?

    Thanks a lot :)
     
  2. borgqueens macrumors member

    borgqueens

    Joined:
    Aug 10, 2013
    Location:
    Denmark
    #2
    I do not have an rMBP but it makes good sense that the battery is draining faster when using more power to show more pixels on the display. So I think your mind is being helpful and not playing tricks.
     
  3. leman macrumors 604

    Joined:
    Oct 14, 2008
    #3
    I have no seen any indication that the power draw would be different between 1400x900 and 1680x1050 (but I also didn't do any measurements). Also, the amount of pixels to display is the same regardless of the scaled resolution (2880x1800). Its true that scaled resolutions require more work from the GPU (texture copying/filtering) but in most scenarios, the increased workload should not have any significant impact on the battery. I can imagine the battery life dropping when you have lots of animations everywhere on the screen for prolonged time, but not with the normal usage (as you only need to redraw parts of the screen where the contents have changed - OS X is incredibly efficient about this).
     
  4. dmccloud macrumors 6502a

    dmccloud

    Joined:
    Sep 7, 2009
    Location:
    Anchorage, AK
    #4
    Since the GPU has to draw all of the pixels regardless of whether it's at "Best for retina" or scaled resolution, the only difference in terms of battery life would be minor, probably not even noticeable. If you were playing a lot of video/animation on the screen, that would have a bigger impact, regardless of the resolution it's being watched at.
     
  5. 5to1 macrumors regular

    Joined:
    Mar 9, 2008
    #5
    Even the "best for retina" involves scaling, perhaps its slightly less complex in some cases as its a straight 2x multiple of native in both directions, but its not a case of simple 1 pixel = 4 pixels. HiDPI involves more then that, otherwise there wouldn't be any benefit of running those modes.

    The only way to avoid any scaling would be to run at native, which I do often and don't really notice a significant difference in battery life. Its what I run, screen brightness, etc which makes the difference. The GPU should be pretty efficient at 2D scaling these days.
     
  6. ste0803 macrumors newbie

    Joined:
    Dec 16, 2012
    Location:
    Gateshead//Newcastle/UK
    #6
    It will drain more battery using a scaled resolution because it actually draws it at 4x the resolution you choose and then downscales that to fit the screen. so if your drawing 1680x1050 its really dealing with (3360x2100) 7 million pixels which will take more strain on the battery than the standard 13" resolution of 1280x800 scaled (2560x1600) which is only 4 million pixels.
     
  7. leman macrumors 604

    Joined:
    Oct 14, 2008
    #7
    And why exactly would it take more strain on the battery? Again: the system only needs to redraw/rescale the changed parts of the screen. Right now, as I am typing this message, this is only few hundred pixels at best (where the cursor is).
     
  8. ste0803 macrumors newbie

    Joined:
    Dec 16, 2012
    Location:
    Gateshead//Newcastle/UK
    #8
    well its having a graphics card drawing 2560x1600 or 3840x2400 the one on the higher resolution will be using more power/ram to deal with the higher resolution so will run hotter and use more power than running the lower resolution.
     
  9. ayeying macrumors 601

    ayeying

    Joined:
    Dec 5, 2007
    Location:
    Yay Area, CA
    #9
    I found literally no difference between scaled and best for retina. I'm getting now 7 hours with VMware Fusion running, running on 1920x1200 HiDPI. If I run it at 1440x900 (Best for Retina), I get the same amount of time but less desktop space to work with.
     

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