Following Apple openly acknowledging the existence of the iMac Freezing issue which plagues users of the latest 20- and 24-inch iMac systems.

Today, Apple released an update aimed solely at users of 20-inch and 24-inch aluminum iMac computers running ATI Radeon HD 2600 Pro graphics cards.

The 772KB can be downloaded from Apple’s website or via Software Update, in the associated notes Apple writes:

This update is for 20-inch and 24-inch aluminum iMac computers with the ATI Radeon HD 2600 Pro graphics running Mac OS X 10.4.10 with iMac Software Update 1.2.1 or Leopard with iMac Software Update 1.3.

And in a further more advanced Knowledge Base article Apple writes:

This update is for 20-inch and 24-inch aluminum iMac computers with the ATI Radeon HD 2600 PRO graphics processor, running Mac OS X 10.4.10 with iMac Software Update 1.2.1 for Tiger, or Mac OS X 10.5 with iMac Software Update 1.3 for Leopard.

It updates the graphics firmware on the ATI Radeon HD 2600 PRO card to address issues that may have caused the computer to freeze.

Not every 20-inch and 24-inch aluminum iMac computer requires this update. If you are not automatically presented with this update, your computer does not need it.

If you manually download this update and attempt to install it on an ineligible computer, you will receive an error message.