It's nothing more than an OEM key or again, pre-activated. Why did I write "again?" The OEM pre-installed OS discussion is rather well done.
And I'm going with no. Microsoft's license system has improved and doesn't seem to work as you wish.
I advise you save your files on the usual backups then restore the Sony and try again.
I have a Sony Vaio SVE14135CXB which shipped with Windows 8. I no longer have my original recovery media. When Windows 8.1 came out, I was prompted every time I restarted my computer to upgrade until I did. This was a horrible mistake. The Sony drivers got screwed up, and I'm now being told I was only supposed to upgrade the special VAIO way- even though my computer only showed me that notification AFTER I had already upgraded. Not only that, but the only way I can revert to 8 is through the original recovery media- which I no longer have- because by upgrading to 8.1, my key was changed to an 8.1 key, and it will not work for windows 8 (It's not written on the bottom of my computer).
So my question is: If I were to download an unactivated version of 8, install all the Sony drivers on it, and then do the PROPER upgrade like they keep telling me I should have done (Seriously, HOW WAS I SUPPOSED TO KNOW THAT?) and then enter my current key, would that work? I would have the additional advantage of not having a whole bunch of sony bloatware, but I'm not sure if this would work/would it even accept my key? Can you upgrade an unactivated version?
Thank you for any help/thoughts you can provide.