We're going to need more info than that. Did you make sure you're on the latest BIOS update for your laptop's motherboard? There should be a dip switch to toggle on the side of your secondary HDD caddy, see if changing positions changes the issue.
Also, you forgot to mention the make and model of your laptop(and it's SKU). A lot of people come around with upgrades done to their laptop then realize that the SATA port is the limiting factor or that the HDD was indeed failing/faulty.