29 Oct iMac (27-inch): AMD Radeon 6970M Video Card Replacement Program
I know that this is old news. But I recently got a call from a customer explaining how their beloved 27″ i7 iMac was producing blocks of vertical green lines going across the screen. This also stopped the Mac OS X from loading. As soon as I saw this in person I knew straight away that it was some sort of graphical error. After a very quick Google search this confirmed my diagnosis.
Apple has determined that some AMD Radeon HD 6970M video cards used in 27-inch iMac computers with 3.1GHz quad-core Intel Core i5 or 3.4GHz quad-core Intel Core i7 processors may fail, causing the computer’s display to appear distorted, white or blue with vertical lines, or to turn black. iMac computers with affected video cards were sold between May 2011 and October 2012.
Additionally, the iMacs must fall in the following serial number configurations. The last four characters of the serial number must contain one of the following groups (example, xxxxxxxxDHJQ) You will find the serial number on the bottom of the stand.
DHJQ, DHJW, DL8Q, DNGH, DNJ9, or DMW8
DPM1, DPM2, DPNV, DNY0, DRVP, DY6F, F610
If your serial number ends in one of the following groups then your iMac is confirmed to have been manufactured with the problem. However here is the catch…
If the iMac (27-inch) meets these requirements, Apple will replace the video card free of charge for four years after the first retail sale of the computer.
However in England you are actually covered for 6 years from the date of purchase/delivery.
So if your iMac is playing up with similar symptoms and falls under one of the serial number group then give Apple a call today as time is quickly running out.