Maybe it's faulty?
Is the BIOS set to the correct drive type?
Check the power and data cables are both properly pushed home at both ends.
Is the data cable fitted correctly? The end near the twist should be on the drive - the other end on the motherboard. Connectors the correct way round. The side of the cable with the red stripe indicates pin1 for connection.
Has the drive worked before, or is this a new-build, or rebuild?