ignore what other people tell you on this
you can install it as many times as you like BUT
you can only activate one copy per license key you have unless you have a family or corporet one that allows multiple computers per key
nearly all windows install disks are the same, if i remove the .cfg file from my disk and reburn it i can install
basic,home,preimium or ultimate from that disk (x64)
i cant install the 32 bit versions but i cant activate them becasue i only have a key for windows 7 proffesional x64
Not true. An OEM has specific licensing requirements that means the OEM is licensed for one computer. There are however certain accommodations that MS has taken into account as I have described. To be able to legally transfer a license at whim under any circumstance the user needs the full retail version. You can install the OEM as many times as you like as long as it is the computer the OEM license is married too. Piecemeal upgrades will be no problems and full upgrades are accommodated by selling the old OEM with the old hardware.