Vista - Driver Load Option doesn't recognize nForce Drivers on CD

I need to load RAID controller drivers on my Dell XPS before the Vista
installation can continue. I downloaded the drivers from Nvidia, unzipped
them and burned them to a CD. I took custom install, and when it came to the
step to select the drive where I want to load Vista, I inserted the CD with
the drivers and clicked the Load Drive option.

It didn't recognize any drivers on the CD. I was expecting a box to come up
and select Raid Class Controller. I can't navigate to the directories on the
CD either.

Any thoughts or suggestions on this problem?
--
Greg