Acer AT310 F1 - Manual (Page 64)

3 System upgrades 46
6 Remove the new processor from its protective packaging.
7 Install the new processor.
(1) Hold the processor by its edges then insert it in the socket.
Make sure that the alignment tabs on the socket fit the two
notches located on the edges of the processor. The pins are
keyed in such a way that you cannot install the processor in
the wrong orientation without bending the pins.
(2) Close the retention plate.
(3) Slide the retention plate tab under the retention knob.