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thelookingglass
Jan 14, 2011, 07:55 AM
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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?



thelookingglass
Jan 15, 2011, 01:46 AM
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No one has this issue except me?

deedas
Jan 15, 2011, 02:47 AM
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.

thelookingglass
Jan 15, 2011, 03:21 AM
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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.

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)

Cerano
Jan 15, 2011, 03:28 AM
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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)

its designed. only one port is "powered"

MacModMachine
Jan 15, 2011, 06:29 AM
its designed. only one port is "powered"

not true , they both provide 500mah,

Cerano
Jan 15, 2011, 06:39 AM
not true , they both provide 500mah,

not true look at this

http://www.pbcentral.com/news/viewnews.cgi?id=EkEpyllyplnoxETCqp

Cerano
Jan 15, 2011, 06:40 AM
http://www.zdnet.com/blog/apple/all-usb-ports-arent-created-equal/1717

your answer

thelookingglass
Jan 15, 2011, 07:12 AM
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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?

MacModMachine
Jan 16, 2011, 01:10 AM
not true look at this

http://www.pbcentral.com/news/viewnews.cgi?id=EkEpyllyplnoxETCqp

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