IIRC, you don't need it unless you are running Windows 95 or 98 (not sure about 98SE).
BTW, Intel has a new proggie that includes the Ultra ATA drivers and it is called Intel Application Accelerator v. 2.0. It's available for download at Intel's website.
EDIT: The Ultra ATA utility is to allow the full usage of the ATA 100 spec.; i.e. harddrive burst speeds up to 100MB per second. Modern versions of Windows have this built in already.