Display distortions/anomalies with 24" 2.4GHz iMac (only when in Windows) GPU issue?

[Chris Welch]

Evening folks. My iMac has exhibited this behavior for a long time. Each time I install a copy of Windows through Boot Camp, this display problem comes up. Often, the experience will be fine. But every so often, the screen will suddenly start to exhibit these graphical problems.

Now what's interesting is that these only happen on the Windows side of things. Back when I originally purchased the machine, it was happening in OS X as well. But Apple released some sort of EFI or firmware update that took care of it over there. No such luck in Windows. Even with Boot Camp drivers installed, it doesn't solve the problem.

Note too that putting the machine to sleep for just a second and waking it will make the problem go away. After a few minutes, it comes back however.

So what could be the culprit here? A GPU issue that only exhibits itself in Windows? Is this something that could be resolved by Apple/the Genius Bar?

Below is a picture of what the problem looks like.

https://dl.getdropbox.com/u/2367088/Mobile Photo Oct 23, 2009 9 20 14 PM.jpg

 

[Chris Welch]

Quite a few views.. Any theories, folks?

 

[nicroma]

Could it be that it runs hotter under Windows and it is leaving artifacts?

 

[Chris Welch]

Temperature certainly has something to do with it. When I had my air conditioner in the room on during the summer, it would rarely happen. Now, at normal room temperature in the fall, it's happening regularly.

Still, a properly functioning graphics card wouldn't be having such severe artifact issues related to heat, correct?

They somehow fixed it on the OS X side. I wish I could do the same in Windows.