Each Windows installation has its own SID. Furthermore, the low-level drivers (such as storage controller) below the NT Executive differ from machine to machine. You can't just swap drives in dissimilar hardware and expect the systems to boot up.
There are workarounds, but you need to know your stuff.
Also, Acronis Universal Restore will restore a system image (made with Acronis Backup) to dissimilar hardware, on both Win servers and wkstns.