Hi, I have a small question. I have an old copy of windows xp professional, 32 bit, that I just installed on my 13" 2011 mbp for playing games. However, even though I am running snow leopard, bootcamp insists that windows 7 is necessary, so I can't install any of the necessary drivers. Now that I know I have to buy windows 7, my question is, which version of windows 7 should I buy? I would like to purchase the 64 bit home premium install if possible, but the main issue is the difference between full retail, upgrade, or system builder. Upgrade seems like the cheapest option, but can I effectively upgrade on bootcamp?