Although Windows XP includes built-in support for most Sound Blaster sound cards, Creative has optimized the drivers for certain models to take advantage of Microsoft's next-generation operating system. This update is intended to provide support for Windows 2000 and Windows XP.
"This is a full driver installation and does not require any previous installation. For a new Windows 2000 or XP installation (as opposed to a system that has been upgraded from a previous Windows version), you may wish to install the applications from your Sound Blaster PCI 512 first and then install this update.
Here's other similar drivers that are different versions or releases for different operating systems: