I bought a 500gb, 7200rpm hd for my notebook. I installed 7 without entering the keycode. Then I re installed it and then put in the key. I didn't get a failed notice, so I activated it and ran wga, so I'm good. I wanted ultimate but where I was at, they were out. I ended up getting a couple of business editions [which I installed],32bit though because msi didn't have 64bit drivers for my model. A few home premium and 2 - 3pack home premium. I figuered if I got business I'd have the xp mode, but from what your saying, it's not all that. My son told me the upgrade version couldn't be loaded without vista on the hd, so I'll send him an email so he knows. One thing I noticed though was the cpu gadgit shows the memory at 1 gig, so it's not as smooth as I thought it would be. I'll have to talk to tech support at msi to see where the 64bit drivers are, I asked them about it last summer for my model and the guy I talked to said they had them but they don't give support if I installed it. Well I'll see how it goes, but anyway you look at it is it's still microsoft.