*Source: AppleInsider (
http://www.appleinsider.com/articles...t ware.html)*
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Evidence is mounting that the frequent video lockups experienced by some owners of Apple's all-aluminum iMacs may be the result of an ATI video chipset pushed to its breaking point rather than a software bug.
One owner speaking to AppleInsider noted that the freezes plaguing his new 20-inch iMac have seemingly vanished ever since Apple replaced the Radeon HD video chipset in the system, suggesting that Apple's recent iMac driver updates are not the ultimate solutions to the issue.
"So far that [repair] has fixed it completely," he says, observing that the iMac has been stable for two weeks since its return. "We'll see if the same issue starts back up again."
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