Source : Engadget On several occasions we have spoken about Apple portables (and this has been the case for a long time) limiting significantly the frequency of their processors if one takes out the battery.
GearLog tells us that it is also the case for the " unibody" machines. Thus, a 2,53 GHz MacBook Pro is 37% less powerful if it runs without a battery installed, only connected to the power adaptor.
This limitation of the frequency is to stop the machine, even during a short moment demanding more power that can be supplied by the power adapter, which otherwise could lead to a fiery end. The battery is useful in these cases by providing the power that the adapter cannot deliver.
Think about this as some of you want to save your battery on a machine which you only seldom move.
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