Thanks Hawkeye4077 for those pics.
Looks like one extra pin is on the am3+ cpu's so they won't fit older am3 boards.

...
/me grabs drill and drills hole in socket, gets dmm and checks to see where extra pin went, hooks up extra pin to whatever and plugs in new cpu, jaja it works .
Just messing...

That msi is mislabled for am3+ support .