Can a new HDD (bigger but same speed) affect battery performance?

Discussion in 'MacBook' started by radicaldog, Mar 24, 2010.

  1. radicaldog macrumors member

    Joined:
    Mar 1, 2010
    #1
    I just switched my old 120Gb drive with a 320gb one (FUJITSU MJA2320BH G2 -- speed should be the same as my old one), and I'm noticing a drop in battery performance of about 20%. Is this just a coincidence?

    Thanks in advance for your help.
     
  2. ViViDboarder macrumors 68040

    ViViDboarder

    Joined:
    Jun 25, 2008
    Location:
    USA
    #2
    It is possible, not sure if it would have a 20% effect though.

    A bigger hard drive will mean that there can be longer seek times. This has the effect of the hard drive spinning up for longer periods of time.
     
  3. gnasher729 macrumors P6

    gnasher729

    Joined:
    Nov 25, 2005
    #3
    Actually, it is the opposite. The drives are all the same size in millimetres, but with the higher capacity drive, the data would be more concentrated in one area. If you have 110 GB used on a 120 GB drive, the drive head has to go all the way from the outside of the drive to the inside to access all the data. Same 110 GB on a 320 GB drive, and only a third is used, so the drive head can stay within the same third of the drive all the time. That's one reason why a bigger drive is faster if everything else is equal.

    It could be that the new drive just uses more power; some drives are better, some are less good. Or that it stops more often when idle and needs to be restarted very often, costing extra power (cheaper to let the drive spin instead of stop/restart/stop/restart). Or it stops less often when idle, wasting energy when the Mac does nothing (cheaper to spin the drive down if it isn't used for ages).
     
  4. ViViDboarder macrumors 68040

    ViViDboarder

    Joined:
    Jun 25, 2008
    Location:
    USA
    #4
    Ah, yea. Didn't think of density being a player. :p
     

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