When the heat sink is inserted into the computer, {HEAD ~ the heat pipe} is disengaged from {TAIL ~ a heat source} 
is disengaged from
When the heat sink is inserted into the computer , { HEAD ~ the heat pipe } is disengaged from { TAIL ~ a heat source }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL