Which Macbook Pro USB port should I use to charge an iPad? I heard that one of the two USB ports provides more power, decreasing the charging time.

Still, I forgot which one is the powerful one. I would be nice to give a hint that's easy to rememeber ;)

It is does matter, this is a MBP from Early 2011, not one of the new 2012 series which has a very powerful charging port.

Update! I checked using System Report (you need to restart it after you plug/unplug iPad as it does not refresh itself).

So far there is no difference on my MBP, it it provides is 500 mA which is quite low.

Current Available (mA): 500
Current Required (mA):  500
Extra Operating Current (mA):   1600
You can use either port, the limitation is that only one USB port can provide this higher power level. If you try and charge two iPads at the same time, only one will get provided with the higher power level, and the decision as to which is made on a first-come-first-served basis.

Edit to Add: I forgot to mention that the article says Macs with more than two USB ports may be capable of powering multiple ports (but not necessarily all) at this higher power level. Unfortunately they don't give any further details.

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