Sorry for the very late response. This is possible if you have Win XP X64. Start the install from Win XP X64 in order to install Win 7 64 bit. I assume that Win 7 32 bit could be installed from Win XP (32 bit), but I never tried that. Boot into XP X64, then run setup.exe from the Win 7 install dvd. When run from Win XP X64, you'll be able to select the install partition by letter, which Win 7 will then retain after the install.