I have some recommendations for you to try:
- First and as mentioned by JFFulcrum, confirm that the two processors have the same core stepping (spec code). As you can see it the following link, there two steps for this processor, C1 (SR0GX) and C2 (SR0KG): http://ark.intel.com/products/64582/Intel-Xeon-Processor-E5-2687W-20M-Cache-3_10-GHz-8_00-GTs-Intel-QPI#@ordering
- If the two processors have the same Spec code then try one unit at a time in the same CPU socket of the board and compare behaviors.
- You can also run the Intel® Processor Diagnostics Tool using one CPU at a time. This tool will report problems or errors if one of the units is malfunctioning. You can get the Intel® Processor Diagnostics Tool using the following URL: http://www.intel.com/support/processors/sb/CS-031726.htm
If you confirm that only one processor is giving issues you better request for warranty. Use the following link to choose the type of service you want and the correct contact center for your area: http://www.intel.com/p/en_US/support/contactsupport