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macrumors newbie
Original poster
Dec 5, 2011
Hey guys,

Lately I have an extremely high CPU usage by kernel task (500+%). I've noticed that I can only reproduce this when 1. connected to an external screen 2. also connected on a USB hub. As soon as I use my Macbook Pro Retina 15" (late 2013 GT 750M) without all the connections the problem goes away.

Might this be caused by the hub?

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Reactions: grahamperrin


macrumors 601
Jun 8, 2007
Yeah, I had that more than once in the past with a MacBookPro5,2. I watched the cleaning by an AASP, it's amazing what gets inside …
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