Apple has failed to respond to a kernel panic issue with the NVIDIA GeForce GT 130 card in 2009 iMacs that has existed for almost a year.

Owners of early 2009 iMacs that feature the NVIDIA GeForce GT 130 video card are experiencing kernel panics, according to reports. 

These are most prevalent with machines running Lion and Mountain Lion, according to a support community thread started almost a year ago.

A screen grab of the issue posted by one user of Apple's fourm

The first post explains that since upgrading to Lion the iMac has experienced the following issues:

  • Pixellation - coloured pixels appear in different areas of the screen, in seemingly random bunches.
  • Mosaics - squares appear redrawn in the wrong part of the screen. Sometimes these squares are large, other times tiny.
  • Recovery - sometimes the system recovers once it starts doing these. Other times it just keeps going until it freezes/panics.
  • Kernel Panics - I've only had the "grey screen" appear once or twice. Usually there is a complete system lockup before this can happen, and I have to reboot the system manually.

That report claims: "OS X Lion's NVIDIA driver kernel extensions (kexts) seem to be faulty with this GPU. The Windows drivers for this GPU work better on Apple's own hardware than OS X Lion's. Anecdotal evidence indicates that Snow Leopard's drivers (at least up to 10.6.3 – more confirmation needed) do not display this issue. I can confirm that this never occurred in Snow Leopard until Lion was released and I upgraded to it."

According to TUAW's report, the issue can be traced to a kernel extension that was released some time ago.

Apparently there is no issue when users funning Windows on the iMac via Boot Camp. "The Windows drivers apparently work on Apple hardware better than the Mac drivers do," notes TUAW.

The most recent posts from yesterday indicate that the issue is still not being addressed by Apple.

In one response from Apple the company states that the iMac is no longer covered by Apple Care and since the company "has no record of reports of the technical issues as described in the customer's letter" they will not be able to replace it.

Last October Apple extended a hard drive replacement program for iMacs containing 1TB Seagate hard drives that have been known to fail. 

Apple first recognized the issue with the Seagate hard drives back in July 2011, but at that time it only included iMacs purchased between May 2011 and July 2011. The original program was originally valid for one year, scheduled to expire 23 July, 2012, but the company has now extended the program until 12 April, 2013. 

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Related: 

Apple admits Seagate hard drive faults in iMacs, will replace