You have a few things happening here, 1st your Windows 7 is probably an OEM (Originaly came w/the system) andassuck is tiedto the original mobo & can'tbe moved.
2nd, you have 1 sys w/ a core2quad processor, and the other has an I5. This means the mobo & memory are different, you have a different setof drivers
so thr=e DX4860 will not boot with the older drivers. Normallythis would take aclean install, but being an OEM version - you would need therecovery discsfromthe DX4860.