Ok so building my mom a new pc and her one has windows 7 on it. This is a retail version of windows 7.the HDD is so old its IDE and wont go in new system plus new one is getting a SSD. My question is since you can now do clean installs with windows 7 keys for windows 10 can i just install 10 be good to go? will this work or will will i have to install 7 and get on the phone with them to activate it and then install 10?