Please verify that your memory meets the specifications as define on page 15, in Section 1.5 of the technical specification:
Provide the EXACT model number of your memory modules.
Also, confirm that the processor is a KNOWN GOOD processor.
Adding to Al's comments, you have listed the memory as being 2Rx8 (i.e. having two ranks). As is detailed in the TPS, 2R (x16) memory is NOT supported.