This 128GB RAM is 100% compatible with ASRock Rack 4U8G-ICX2/2T.

Information on memory configuration: The following technical specifications should be considered in advance: RDIMM and RDIMM 3DS (Registered DIMM) or LRDIMM and LRDIMM 3DS (Load Reduced DIMM) RAM can be installed in the device. LRDIMM memory is recommended for achieving large memory capacities. RDIMM and RDIMM 3DS memory modules cannot be mixed with LRDIMM and LRDIMM 3DS memory. If a memory expansion is to be made with the existing RAM, it must be checked which base memory technology (RDIMM / LRDIMM) is present. When using a multiprocessor system, the memory slots should always be populated identically for each CPU. Memory slots without a processor should not be populated. If memory modules with higher clock rates than specified by the system are offered, the memory clock will automatically adjust to the system specifications.

Maximum memory speed of the possible CPUs: Xeon CPUs of the 3rd generation are offered as Silver, Gold, or Platinum. The different processor series support different maximum clock frequencies:

Xeon CPU series max. Speed MHz max. Memory capacity per CPU
CPU xxxxH 4300 2666 TB
Gold 5300 2933 TB 1.2 TB 4.5 TB
Gold 6300 3200 TB 1.2 TB 4.5 TB
Platinum 8300 3200 TB 1.2 TB 4.5 TB.