Acer AcerAltos 21000 System Manual page 73

4. Insert the Pentium II Xeon processor into an empty Slot 2 socket.
OO
5. Carefully press down the Pentium II Xeon processor until it is
properly inserted.
6. Use the retention mechanism cover to secure the processor as
shown below.
The retention mechanism cover only fits one way. Both shafts of
the retention mechanism and the retention mechanism cover
have a O and a OO sign. Match the O on the cover with the O
on the retention mechanism first, then hooked them together and
then insert the OO side to the retention mechanism and make
sure they are clipped.
System Boards 3-9