Have you been into the BIOS to make sure it's there and detected?
Once the BIOS knows about it, it should appear in My Computer and you will be bale to format the drive from within windows which is much much faster than Fdisk (which formats at the speed of the floppy for some reason)
Post here if you need help getting into your BIOS, and what sort of BIOS you have. Award, AMI etc.
click here for an overview of BIOS if you need it.