I am going to download Win 8 and install it as an upgrade to an existing Win 7 oem on a Toshiba Laptop. I have run the pre- assessment tool and the result was OK. I want to do a fresh install of Win 7 prior to upgrading, I have the disk's to do that. Will I have to update the fresh install including the service pack prior to upgading to Win 8 ? or can I just upgrade the fresh installation ?