When {HEAD ~ the heat sink} is removed from {TAIL ~ the computer}, the heat pipe is engaged with the heat source to transfer heat generated by the heat source to the heat sink, which is external to the computer 
When { HEAD ~ the heat sink } is removed from { TAIL ~ the computer } , the heat pipe is engaged with the heat source to transfer heat generated by the heat source to the heat sink , which is external to the computer
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH