I'm thinking of upgrading my laptop that came with Windows 8 x64 O.E.M. and has been upgraded to 8.1 x64 to 8.1 Pro x64 over the weekend.Can I do a clean install of 8.1 Pro with the product key that Microsoft give's me with the 8.1 Pro upgrade. I already have 8.1 Pro on a usb flash drive that I've used for clean installs on my desktop pc. Afterwards, I've alway's gotten the updates, including 8.1 Update afterwards. I'd love to be able to do the same on my laptop and start completely fresh, minus all the extra partitions Asus added. I know their supposed to be 3 partitions if you have a u.e.f.I., but my laptop has 2 more created by Asus. Those 2, I'll never use, as they're for Windows 8.