Apple on Friday began a new program to replace faulty graphics cards found in some mid-2011 to late-2012 iMacs.
The program covers systems with AMD Radeon HD 6970M video cards. Those were found in the 27-inch iMac models with either the 3.1GHz or 3.4GHz quad-core Intel i-series chips.
According to support language, the video cards could fail, "causing the computer display to appear distorted, white or blue with vertical lines, or to turn black."
was sold between May 2011 to October 2012.
The program overlaps with an earlier replacement program covering Seagate hard drives found on some iMacs.
Details of the program were posted earlier Friday by 9to5Mac.
Updated at 8 p.m. PT with additional details and link to replacement program page.