I'm building my first rig and for the first time in my life I have to install an OS (Windows in this case) on my own. I know the quickest way would be to put a cd with the iso in it and set boot priority to the cd drive. The problem is I'd rather not waste money for a drive, so is there a way to install Windows (was thinking about 8.1) on a clean PC without using a cd? Don't know if it might help, but I'm planning to buy a product key from key sellers like G2A, don't know if it changes the process a bit.