The usb port from my external 500gb hard drive broke, when I opened the case inside is a regular desktop hard drive. I bought some sata cables to retrieve the data but when I hook it up to the computer nothing is displayed on my computer. I do see that the computer is reading it or atleast see's it under the disk management, it says 465 Gb unallocated. How do I fix this problem, I need to retrieve the important data on hard drive. Thanks