Asus M2N4-SLI - Manual (Page 26)

2-6 Chapter 2: Hardware information
3. Position the CPU above the
socket such that the CPU corner
with the gold triangle matches
the socket corner with a small
triangle.
5. When the CPU is in place, push
down the socket lever to secure
the CPU. The lever clicks on the
side tab to indicate that it is
locked.
6. Install a CPU heatsink and fan
following the instructions that
came with the heatsink package.
Gold triangle
Small triangle