Allister Gray

Good Morning Hope someone can help me with this. A while ago (probably around 2 or 3 years ago now) I got a Seagate 1TB external hard drive and the case broke where the usb connects in the computer. I took it out the case since the case was no use anymore and the warranty was finished. I can connect into my computer internally and it seems to work fine, however I have only 2 SATA ports so I couldn't have my DVD writer connected. I got a 2.5" connector and it fits into the drive perfectly and the light shows that, however there is nothing showing up on the computer, I am running Windows 7 Home Premium edition. Do I need to get a bigger external bay for it to work? Or is there anything I can do? If I do have to get a new drive bay, what is the best and cheapest? Thanks in advanced for your time :)