They look great - but why are new iMacs so problematic?

The new aluminium desktop iMacs launched by Apple in August are an ornament for any workspace. Sadly, their looks may be their best feature. "Loaded with iLife," the company promised.But Nicola Killen is one of numerous owners who has spent three months trying to breathe life into her glamorous screen. "The cursor moves about," she says, "but nothing else works." Programs continue to run but Killen and other users have found their screens frozen.

Apple admitted this handicap at the beginning of October and produced a software update to solve the problems. It did not. In fact, according to Killen and various chatroom posts, the solution made things worse. "Apple insists it's a software issue, but it seems likely that there are issues with the graphics card in some machines," she says. "I've tried all the suggestions from the Applecare helpline, but to no avail."

Apple seems unable to apologise, or explain why it has left customers frozen for so long. However, it has now launched a graphics firmware update to be automatically downloaded on affected machines. This appears to have improved Killen's iMac but she is still frustrated at Apple's response.

"A lot of people spent weeks on the phone and internet trying to get their computers working," she says. "As a student with only a mobile phone, I found all these calls very expensive and was taken through hours of hardware tests and reinstallations of the hard drive to no avail. By this stage they must have known what the problem was."

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