Hello I recently bought the sandisk ssd to upgrade my old hard drive on my gaming pc but when i unplugged my hard drive and plugged my ssd it didn't read my ssd.. Why is that happening is it not working? This is my setup. Evga 970, i5 4690, Gigabyte z97x, and sandisk 120gb ssd. And im trying to install windows 8.1 and use the old hard drive for my games and stuff. Thx! Also in BIOS it reads the drive but when I try to install windows on it it doesn't show up.