28 minutes ago, seoz said:
My process is as follows:
- Take out Samsung 850 Evo
- Put in Crucial P1
- Insert Windows 10 USB key
- Install Windows 10 onto Crucial P1
- Insert Samsung 850 Evo after install is complete
- Format Samsung 850 Evo to get both the Crucial P1 + Samsung 850 Evo working in tandem
That's 100% correct.
29 minutes ago, seoz said:
Also, it's a storage upgrade only, so in theory if I sign into my Microsoft account, I should still have Windows 10 activation, right?
Linking your Windows key to your Microsoft account is a good idea. This guarantees that you can activate Windows 10.
Here's how to do it: https://www.windowscentral.com/how-re-activate-windows-10-after-hardware-change
Usually, Windows will remain activated if you change your storage but not your motherboard, but do as I said above just to be safe (so you don't need to buy another Windows activation key).