Hi actually have two questions,1. How many times can I reinstall Win 7 OEM (Full version) on my DIY computer, say I do not change my motherboard and harddisk?2. If I upgrade my graphics, would that invalidate my installation of Win 7?Thanx in advance.

As long as it's being reinstalled on the same computer/motherboard you should be able to do it as many times as necessary. Telephone activation may be required. Replacement of the graphics card, and no other hardware change at that time, would probably not invalidate the installation. Again, if it does, telephone activation may be required but is not a big deal taking only 5 or 6 minutes usually.

Thanks. Appreciate that.Cheers.