Now, I actually have the exact same OEM disk of Windows 7 Home Premium installed. I have a sister that seems to think she owns my laptop. I have considered splitting my HDD partition into 2 so that I can have my own installation and part of the drive. The problem is that if I screw something up, my sister will have a cow (it's the only place where she stores her iTunes, etc. and she's stubborn to use anything else, she wouldn't even accept it on backup). Can I also have 2 of the same OEM copies on each partition? If not, I'm Out of luck.