Any idea what this is caused by? It's a 27" iMac Mid 2010.
Sorry for the animated GIF, but Apple has disabled video embedding. (Click to play)
Turns out it was a bad graphics card.
Called AppleCare and they sent someone out to my house. Replaced the graphics card AND the whole LED display — over $1600 in repairs! For free! (well, the cost of AppleCare)
If you ever question the value of AppleCare, just this one repair almost cost the same as my iMac. So it's a pretty good deal in my opinion!
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