I have a server with Supermicro H12SSL-NT MB, all 8 memory channels populated. CPU is EPYC 7302P. The STREAM Benchmark shows a result of<100GB/s where I expect >16GB/s. All BIOS settings seem correct, the memory is clocked at 3200MHz.
A second server that I am comparing with a different MB but same processor and memory config does perform accordign to expectation.
Any hints as to how to solve this or what setting I might be missing, would be welcome. I cannot believe that on the Supermicro MB the memory channels would be incorrectly connected such that the 8 DIMMS actually connect to only 4 channels....
Edit: Here is Microcenter's Specs on your motherboard. It also has it own QVL List for the processor you are using.
The Ram List only shows one compatible RAM MEMORY for the 7300 Series EPYC Processor: https://www.supermicro.com/en/support/resources/memory?mspd=3.2&mtyp=139&id=5c6c2cbf8d4c88c585d9b4b3...
Also see if you have the latest BIOS Version installed on your motherboard. you can download it from the link above:
NOTE: When I went to check on what Drivers it had to download it only had 2 Server type OS Compatibility:
Windows Server 2016 and 2019.