Hi I have purchased a Lenovo desktop Thinkcenter with Windows 7 PRofessional 64bit pre installed. I needed some test applications that run only on 32 bit platform. So I need to install Windows 7 Professional 32 bit. I do not have any any installation media from lenovo. So Do I need to buy a fresh retail Windows 7 32 bit professional OR Can I use ANY windows 7 professional 32 bit retail version DVD for installation and then product key on the windows 7 preofessional 64 bit sticker on my thinkcenter? Is this legal? Is it allowed by microsoft?