General information for how to populate memory on dual-socket Intel® Server Boards
How to properly populate memory modules on dual-socket Intel® Server Boards?
As a general rule of thumb, for each installed CPU, correspondingly populate the blue slots first, starting from the slot farthest from the processor.
Refer to the Memory Subsystem section of the Technical Product Specifications (TPS) document for your particular dual processing Intel® Server Board for the complete memory population rules.
Additionally, it would also be important to check into the tested memory list. Therefore, you ensure that you use officially validated memory on your board.