Apple has posted
GeForce 7300 GT Firmware Update, intended for users of Mac Pro systems equipped with graphics cards that use Nvidia’s GeForce 7300 GT chip.
The 2MB download — available from Apple’s Web site — updates the firmware on all of the Nvidia GeForce 7300 GT cards in the Mac Pro (users can install more than one such card in the Mac Pro, as it uses PCI Express). The firmware update application is moved into the Application/Utilities directory.
Apple does not offer any additional details about what changes are made by this firmware update, so please proceed with caution.
System requirements call for a Mac Pro and Mac OS X v10.4.7 or later.