Update part II
I have contacted microsoft support about this issue and the plot thickens
Basically my issue is that the pc came prepackaged with win 7 which was later upgraded to win10
Support asked for my key, but the only one i could provide was the win 7 key that is stickered to the side of the pc
So i can confirm that
the win 10 key is always based on your mobo
(this was confirmed by winsupport)
But here is the weird part;
They stated that i could use the win 7 key to install win 7 and that i MIGHT be able to upgrade to win 10
They also said that it would no longer be free
But they remained vague on wether it was possible to upgrade from win7 to 10
(maybe based on hardware, don't know, forgot to ask
)
I did ask wether he would be able to provide me with a key if the pc came shipped with win 10
(instead of win7)
And the answer is;
If you have a Windows 10 preinstalled on your system, it came embedded in the motherboard we can easily fetch the key through WMIC command.
If you do not have the key also your OEM will help you in retrieving the product key of Windows 10.
CONCLUSION
So i guess a lesson to learn here is that it is best to extract your key from your pc for future use, before your hardware gives out
Also i learned that it is indeed possible and legal to thusly transfer your win 10 license, provided you have your key
(For those interested i can provide the whole chat transcript)
weirdly enough as a last note the guy seemed to urge me to try it nonetheless
as if there is some loophole where you can still do the process for free (?) anyone familiar with such a thing?
this is what i found on the subject
https://www.howtogeek.com/272201/all-the-ways-you-can-still-get-windows-10-for-free/
phew, what a journey