I purchased an ASUS laptop with an OEM Windows 8 Pro (not 8.1) OS back in December of 2012. Windows 8 Pro came pre-installed on the single HDD that was in the laptop. Since then I have upgraded to Windows 8.1 and have also purchased the Windows Pro Media Pack license key which is now installed on the HDD. So my current state on the HDD is Windows 8.1 Pro with the Media Center.
Now, the laptop has a place for two hard drives and I recently purchased an SSD drive and installed it in the second slot. My goal here is to install Windows 8 using my original OEM key on my new SSD drive and then wipe my old HDD clean.
I know that Windows 8 and 8.1 have different product keys. I also know that my OEM key is stored on my UEFI, which I was able to retrieve using a few of the tools supplied in various posts on the forums here. I downloaded the Windows 8.1 Media Creation Tool, chose Windows 8.1 Pro, and created an ISO. I then installed Windows 8.1 successfully on my SSD using the generic OEM key found in one of the other posts. However, when I go to activate my original Windows 8 Pro OEM key that I got from my BIOS it says the key won't work.
What am I doing wrong here? I've been scouring this site for a few days now and have tried a few other approaches but to no avail. It seems like if this route won't work then I could get things working with a true Windows 8 Pro (not 8.1) ISO, but I can't find one anywhere that isn't shady, and Microsoft seems to have removed their Windows 8 (not 8.1) setup downloads from their site (although they used to have one because I've seen screenshots of it in a post on a different forum).
I'm willing to provide any more information needed and retry any of the steps in any order recommended. I have a legal OEM key...it seems like I should be able to legally install Windows on a new drive on the same machine.
Thanks to all who help!