I agree that installing a new OS, or any upgraded program, on top of an existing install of an older OS/program is bad practice. Heck, how many times has it been stated on this site alone that the best way to do a video driver update is to uninstall the old drivers, use a driver sweeper to remove any left over fragments of the old drivers, then install the new drivers.
I would have no problems installing Win 7 as a totally new OS onto a formatted HD. There are those who are computer users who do not have the computer know how to do this, but those are the people that Geek Squad is in business to provide services to....although I have not spoken to a Geek Squad person who seemed to really know his stuff...I have gotten better help simply by asking questions here on SOH.
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