Apple has determined that some video cards AMD Radeon HD 6970M used in computers 27-inch iMac with Intel i7 quad-core 3.1 GHz processor and 3.4GHz Intel i5 quad-core processor may have problems, causing computer display distortion that may appear with white or blue stripes with vertical lines, or it may become completely black . The iMac computers with the affected video cards were sold between May 2011 and October 2012.
AppleCare, Genius Bar and Apple Authorized Resellers have been commissioned to check if customers' iMacs highlight the known problems of the graphics card. Below we offer a YouTube video that demonstrates some of the problems that have emerged.
The defects have been documented over the last two years on Apple's own Support Forums and the iMacs, to be included in the program, must have the following serial number combinations:
The last four characters of the serial number must contain one of the following groups (for example, xxxxxxxxDHJQ):
DHJQ, DHJW, DL8Q, DNGH, DNJ9, or DMW8
DPM1, DPM2, DPNV, DNY0, DRVP, DY6F, F610
If the iMac falls into one of the serial number categories listed above and you have verified that you have the known problems with the graphics card, Apple will replace the AMD card free of charge up to three years from the date of purchase of the computer. Furthermore, if an iMac user had already replaced the graphics card of his iMac for a fee, the customer will be reimbursed.
This is not the first time that iMacs have been affected by problems related to internal components. Late last year, Apple announced a hard drive replacement program for iMacs sold between 2009 and 2011.