Dell Vostro 220s (Late 2008) - Manual (Page 127)

Processor
127
NOTICE:
Socket pins are delicate. To avoid damage, ensure that the processor is
aligned properly with the socket, and do not use excessive force when you install
the processor. Be careful not to touch or bend the pins on the system board.
2 Pivot the release lever fully and ensure that the processor cover remains
raised.
3 Orient the two alignment notches on the processor with the two alignment
notches on the socket.
4 Align the pin-1 corners of the processor and socket, and set the processor
lightly in the socket, ensuring that the processor is positioned correctly.
1 tab 2 processor cover
3 processor 4 processor socket
5 retention latch 6 release lever
7 processor pin-1 indicator 8 alignment notch
9 retention hook 10 alignment notch
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