(As I am still new to hardwarerecs, I cannot post more than 2 links.)

I am to purchase RAM for my newly purchased

• ASUS P10S-M WS/IPMI-O that supports 4 x DIMM, Max. 64GB, DDR4 2400/2133 MHz ECC, Non-ECC, Un-buffered Memory Dual Channel Memory Architecture
• and Intel® Xeon® Processor E3-1260L v5 that supports 64 GB DDR4-1866/2133, DDR3L-1333/1600 @ 1.35V ECC

I want to max out the memory to 64GB and planned to puchase four

• 16GB ECC unbuffered/UNB/UDIMM RAM.

The memory I am interested in is

• Samsung 288pin DDR4 Unbuffered DIMM based on 16Gb (M391A2K43BB1-CPB)
• (http ://www.samsung.com/semiconductor/products/dram/pc-dram/ddr4-unbuffered-dimm/M391A2K43BB1?ia=2428)

The question is whether the SAMSUNG memory is compatible with the ASUS motherboard.

Samsung's Support > Tools & Utilities > Board Compatibility is not helpful, and strangely does not even list DDR4 memory.

• http ://www.samsung.com/semiconductor/support/tools-utilities/board-compatibility/

The QVL (Qualified Vendor List) for memory from ASUS does not list M391A2K43BB1-CPB.

• http ://dlcdnet.asus.com/pub/ASUS/mb/socket1151/P10S-M_WS/QVL/ESC500_G4_SFF_ESC510_G4_SFF_Series_Memory_20170929.pdf

Two other Samsung memories are however listed 16GB DDR4-2400 Non-ECC/UNB and 8GB DDR4-2133 ECC/UNB CL15; the first not fit for the CPU, and the second will only max out to 32GB.

The only two vendors that are on the list with an acceptable memory specification 16GB DDR4-2133 ECC/UNB CL15 are INNODISK and Skhynix. Neither of which are available to me for purchase.

I found however that the QVL for memory for the ASUS P10S-M motherboard lists the Samsung M391A2K43BB1-CPB.

• https ://www.asus.com/Commercial-Servers-Workstations/P10S-M/HelpDesk_QVL/

I noticed that the memory chip for the listed Samsung M391A2K43BB1-CPB is the same memory chip listed for the INNODISK memory chip; Samsung K4A8G085WB-BCPB.

There are multiple memory companies on the market, but only a few true memory manufacturing companies. When researching different memory brands, you may run across companies that claim to be memory manufacturers, when they're really just module assemblers. How these companies work is that they purchase pre-manufactured parts (such as DRAM chips and printed circuit board) from true memory manufacturers, and then assemble these components to “manufacture” a module with their label on it.

• http ://www.crucial.com/usa/en/store-truth-about-memory-manufacturers

If I understand correctly, the listed P10S-M WS/IPM-O INNODB M4CR-AGS1MC0G-BE93 is actually more or less the same memory as Samsung M391A2K43BB1-CPB?

Even if they would differ for some reason, I am having a very difficult time to accept that the M391A2K43BB1-CPB -- or really any other memory -- will be incompatible with the motherboard save for some edge cases, such as incorrect manufacturing or assembling.

As this is my first build it would be assuring if someone would confirm my conclusion.