Hi Billy,
Welcome to PCHF.
There are a few it could be, 476, 775. It will normally show the socket number on the socket itself, which you can see when you remove the fan. Otherwise, to know for certain, download and run SIW:
http://www.gtopala.net/en/siw.exe
Scroll down to Hardware > Motherboard. You will see your
CPU Socket there.