Apple has responded to our story yesterday about screen freezing problems with the latest generation of iMac desktop computers. Some have said that dodgy drivers for the ATI Radeon HD graphics cards used in the iMac may be to blame. However Apple neither confirmed, nor denied this in its statement today. The full text reads:

"A small number of iMac users have made us aware that a recent software update issued by Apple can sometimes cause their iMacs to freeze, requiring them to restart their iMac. We are tracking down the root cause of this bug, and will issue a software update which corrects it as soon as we can - most likely later this month. We apologise for the inconvenience."

Firmware update

iMac users experiencing problems have been sharing their thoughts on Apple's own Discussion Forums. And some appear to have experienced problems before the iMac Software Update 1.1 that is currently under scrutiny at Apple.

The problem appears to be sporadic and erratic, with some users reporting many freezes per day, and others only one or two. Some freezes appear to be triggered by certain applications such as iTunes or Adobe Photoshop. Others cause no problems at all.

The freeze apparently manifests itself by locking up the screen, even though applications continue to run and users can move their mouse cursor around. However, affected iMacs don't appear to respond to keyboard presses or mouse clicks, forcing users to restart their iMacs.

We currently have a 24-inch iMac on test and have experienced no problems so far. However we'd love to hear from you if you're having experiencing iMac freeze issues.