Some owners of early 2009 model iMacs that have upgraded to later versions of Snow Leopard, Lion or Mountain Lion have been reporting issues with the included Nvidia GeForce GT 130 video card without a response from Apple, according to a year-long support thread on the company's support website. The issue appears to center around a faulty kernel extension released late in the Snow Leopard updates that remains unfixed, and causes graphic glitches, crashes and even kernel panics when the graphics card is stressed, such as during games.
