How to Install Driver with a cat file?

In Windows Vista and Windows 7 there a new utility for handling drivers setup call PnPUtil. It handles exactly this kind of work. Just copy all your driver relevant files(*.inf, *.cat, *.sys) to a directory on the target computer and use PnPUtil -i -a <InfName>.inf

Note: You will need to be in an administrator context to successfully use this tool.