Good deal. Was an engineering sample, as described. Used the Intel Processor Diagnostic Tool (freely downloadable from Intel) to verify that it was authentic.
Note that because it is an engineering sample, it will fail the SPBC test. According to the Intel Processor Diagnostic Tool manual, SPBC = Sample Production Bit Checker. “The purpose of spbc.exe is to determine if the processor under test is either a sample or production processor.”
I have read that engineering samples may run slower and/or hotter than production chips, so YMMV.