Some mid-2013 iMacs Feature Faulty GPUs
 

Apple announced a GPU Replacement Program along the lines of its HDD Replacement Program, dating back to 2011, for mid-2011 iMacs, which had its run at the markets from May 2011 to October 2012, more specifically, iMacs equipped with AMD Radeon HD 6970M. Apple says that both the 1 GB and 2 GB variants of the graphics boards inside these iMacs could fail. Telltale signs include artifacts on the screen, including white or blue vertical lines or a solid black display. Apple is offering free repair and replacement for affected iMacs, and refunds to people to paid to get the issue fixed, prior to this announcement.

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