Stefan Mileschin

Users of 2011 15-inch and 17-inch MacBook Pros are finding that their AMD graphics processors are letting them down and that they need a $500 logic board replacement.

Several threads on Apple's Support Communities forum suggest that the problem presents itself as a graphical glitch or complete system lockup.

The problem appears to be caused when the MacBook Pro switches from the integrated Intel graphics chip to the discrete AMD GPU.

According to Apple Insider, the first problems cropped up in February, but are increasing.

What appears to have happened is that Apple introduced the automatic graphics switching system, which shifts the processing load between the integrated chip and the discrete GPU based on what the user is doing.

First users get display discoloration, banding, and image distortion, but others say that their computers suddenly freeze without any warning. Rebooting rarely fixes the problem.

The majority of affected users are using early-2011 MacBook Pros with the AMD Radeon 6750M GPU. However failures are not limited to that chip as those using the Radeon 6490M, 6750M, and 6970M GPUs are also experiencing the problem.

Of course Apple has been slow to respond and have been telling users without AppleCare that they will have to buy a new logic board which will set them back $500 or more. They are also treated to a stare from the Apple Genius as to why they owned such an old laptop when the true Apple religion demands a yearly upgrade.

Apple 2011 laptop range appears to be mourning the death of Steve Jobs, with problems on the models now stretches over more than 140 pages with over 2,000 replies on one site alone.

http://news.techeye.net/chips/amd-ch...nking-headache