About ATI Radeon HD 2600 XT Firmware UpdateThis update is for Mac Pro computers with one or more ATI Radeon HD 2600 XT graphics cards installed, running Mac OS X 10.5.2 or later with the Leopard Graphics Update. It updates the ATI Radeon HD 2600 XT graphics card firmware on all of the ATI Radeon HD 2600 XT graphics cards in the Mac Pro to improve system stability.Link is here.   Apple Support