can you post some pics of the pc so i can see? You should be able to get a new HD, same size and type as other, and in bios raid 0 it, and then boot UEFI to USB and install windows
post your full system specifications so we can search google and see how to do it. raid is not even a good solution for most purposes, can I ask why you run it? are you running an Oracle Database or something? There are better ways to join two disks
Reason I hate two drive Raid0, you lose ONE drive, BAM, your dead. I like ONE install drive. if it fails, I can put in another and install windows in 8 minutes via usb, your raid really doesn't buy much in terms of performance gains anyway, hdd or ssd. in short, it is a huge pain in the arse, and doubles your...