Uneven USB power output

Discussion in 'MacBook Air' started by thelookingglass, Jan 14, 2011.

  1. macrumors 68000

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    #1
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    Seems my left USB port outputs more power than my right. Certain devices charge fine on the left but not on the right. Do you guys have the same issue?
     
  2. thread starter macrumors 68000

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    #2
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    No one has this issue except me?
     
  3. macrumors regular

    deedas

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    #3
    I have an issue with the USB ports on my air but it's not what you have. I do remember a while back Apple shipped laptops which had one high power usb port, and one or two other low power ones. With the Airs, it wasn't until this gen that we got more than one USB port. Before there was only one and it was high power to be able to send enough juice to the external dvd burner. It could be that we only have one high power one as well today. I'm just speculating. I have no evidence to back this up right now.
     
  4. thread starter macrumors 68000

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    Thanks, interesting. That's actually what I'm trying to figure out - is this intentional or do I have a faulty UBS port? Seems like from what you mentioned this unequal power output may have been intentional in the past (although I can't figure out why they'd do that - the gains from saving power don't seem to be significant enough to warrant crippling one port)
     
  5. macrumors regular

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    Oct 28, 2010
    #5
    its designed. only one port is "powered"
     
  6. macrumors 68020

    MacModMachine

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    Location:
    Canada
    #6
    not true , they both provide 500mah,
     
  7. macrumors regular

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    Oct 28, 2010
    #7
  8. macrumors regular

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  9. thread starter macrumors 68000

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    #9
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    Thanks, that's helpful to know. The next question, naturally, is why does Apple do this? And is this the case for all notebooks or just Apple's?
     
  10. macrumors 68020

    MacModMachine

    Joined:
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    #10
    great for posting a OLD as hell articles with no relation to the subject, this a is a macbook air not a macbook (pro) the is air which have significant power differences on the usb ports to accommodate the USB superdrive


    i measured both with a multimeter for output, THEY both put out 500mah
     

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