Dell XPS 8500 (Early 2012) - Manual (Page 104)

3 Orient the alignment notches on the processor with the alignment tabs on
the socket.
4 Align the pin-1 corner of the processor with the pin-1 corner of the
processor socket, and then place the processor in the processor socket.
Set the processor lightly in the socket and ensure that the processor is
positioned correctly.
1
2
1 processor 2 socket
Processor 104