Can't Find Second Drive In Win8

I just bought a new computer with W8 installed. This is a big step from XP that I've been running for quite a while. I had two drives (both 500Gb) in the old box, and I'd like to use them in the new. When I try the old drive with boot tracks as an internal - the new box has three spaces for HDD internally - the computer won't even boot. Once I remove the drive everything is back to normal. I have a USB3 external drive case that I installed the same drive in, and, although W8 recognizes I have a USB3 device connected, it's as if there's nothing inside. I've tried doing what I'm told in Devices and Printers (right-click, etc.) but still nothing. The one thing I do see is "Drive E:" in a shaded box to the right of the description, but I can't click on it. Since the drive has five drive assignments (C: through G, I would think whatever happens those assignments would show up in a description of the drive. I don't get anything. I would think as long as I don't try to boot from the old drive (via boot from external, etc) the boot tracks on the drive would not have any meaning - right?

I would like to be able to use some of the software I've downloaded in the past and installed on the XP computer. That's the main reason for trying to use the drive. All the software I downloaded is located in one of the virtual drives (G, and I want to copy off those that are of value to me now.