Back in July 2008, NVIDIA publicly acknowledged that it had a higher than normal failure rate for some of their graphics processors due to a packaging defect. After the announcement NVIDIA agreed to pay up to $200 million to cover the whole case and repair, return or replace the faulty chips. At the time NVIDIA admited the high failure rate, it also assured Apple that Mac computers with these graphics processors were not affected. However, after an Apple-led investigation, today Apple has determined that some MacBook Pro computers with the NVIDIA GeForce 8600M GT graphics processor may be affected after all. If the NVIDIA graphics processor in your MacBook Pro has failed, or fails within two years of the original date of purchase, a repair will be done free of charge, even if your MacBook Pro is out of warranty. Here's what to look for in your Mac, if you receive a distorted or scrambled video on the computer screen or in the worst scenarion if you have no video signal on the computer screen (or external display) even though the computer is on, you should immediately go to an Apple Retail Store or an Apple Authorized Service Provider (AASP) for evaluation, or you should call your local Apple Contact Center for help. Among the models affected are those that were manufactured between approximately May 2007 and September 2008. They include the following models: MacBook Pro (15-inch, 2.4/2.2GHz), MacBook Pro (17-inch, 2.4GHz), and MacBook Pro (Early 2008).

Source: Apple