Hey Im building a new pc and I plan on using all new parts except hard drive because Im trying to save all of my data. Ive been reading online and have come across some information saying that it could possible work but it might effect activation. Would I be able to buy a new key and use it on first boot up. or would I have to get a fresh install.
Yes, the digital entitlement feature of activation will be lost due to the new hardware but you may still be able to access your Microsoft Account and get activated, at least it worked that way when my older computer crashed. And Yes, it should be possible to purchase a new key if the other way doesn't work. Just be sure it's the same as presently installed, Home or Pro or ???.
Home and will I have to remove all the old drivers with sysprep before moving it to the new pc?
I didn't but the motherboards were the same brand. But you should get an Optical Disc with the new board that has the necessary drivers, at least for the Network adapter/s so you can get online right away to get other necessary drivers.
In all my time of installing I really think you are better off installing a fresh copy on a fresh / or securely wiped hdd / ssd.
It only takes 15 mins to load up to win desktop more or less on a good stable mobo, just copy all you data to a usb stick or external hdd/ssd, I'm sure everbody does not agree but fresh mobo / fresh copy of windows?
Windows 10 is much more tolerant of moving between computers than previous versions of Windows have been. HOWEVER, that being said, if I was @manitty, I would use this as an opportunity to put an SSD in the new computer and after installing Windows 10 fresh to it, connect the old hard drive for data retrieval and as an eventual data storage location.
As stated by @Berton, if the previous login to the old computer was with a Microsoft account with the latest version (1607) of Windows 10 running, then the digital license should be linked to the Microsoft account and should be able to be retrieved by running the activation troubleshooter on the new computer, once logged into the same Microsoft account.
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