Fresh Windows Install & Reinstalling Cubase

I’ve recently been having some unexplained BSODs on my computer, and having failed to identify which driver is causing it, I’ve decided to do a fresh windows install instead.
I bought cubase 7 a year ago, I was entitled to the free 7.5 upgrade and everything is licensed to the eLicenser, linked to My Steinberg account and all that.
My install disks for cubase are in a different city to me and i won’t be able to get to them for a month or so, this includes the product key on the box. Can I reinstall cubase from the iso provided on the website and just activate it somehow through my eLicenser, or will i have to put the code in as well? As much of a pain as it is to have my computer randomly crash out halfway through doing something, it would be more of a pain to have no cubase at all…