This update is recommended for all iMac (late 2013) models.
This update is recommended for iMac (late 2013) models. This update addresses an issue which may cause a black screen to appear when installing Windows 7 or Windows 8 using Boot Camp Assistant if both an external optical drive and USB thumb drive are connected to the system. This update also ensures that the system will boot by default into OS X after installation of Windows 8.
Mac OS X 10.8.4 and greater
Here's other similar drivers that are different versions or releases for different operating systems: