NEC 140He - Manual (Page 318)

9-60
9. Put the processor on the socket slowly and gently.
NOTE: Make sure of the orientation of the processor. Pin layouts on two corners among
four differ from others to prevent an incorrect insertion. Confirm the pin mark and pin
layout on the socket, and insert the processor correctly.
Pin mark
10. Push the processor lightly to the socket, and push down the lever to secure the processor.
11. Remove the cooling sheet from the bottom of the heat sink, and put the heat sink on processor.
NOTE: You do not need to care of the direction of heat sink.