Personally, I would return both.
Both the board and cpu are out of support:
http://ark.intel.com/products/40078/Intel-Desktop-Board-DP55WG
http://processormatch.intel.com/CompDB/SearchResult.aspx?BoardName=DP55WG
The processor does say that minimum bios is 5531. How you get there is the issue. And, you may still be left with a problem.
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