Dell PowerEdge R940xa — supported memory

4-socket 4U GPU server. 48 DDR4 DIMM slots (12 per CPU), 6 memory channels per socket, 2 DIMMs per channel. Supports RDIMM and LRDIMM (registered ECC DDR4 only; RDIMM and LRDIMM must not be mixed). Up to four Intel Xeon Scalable processors: 1st Gen (Skylake) validated up to 2666 MT/s and 2nd Gen (Cascade Lake, Gold and Platinum, up to 28 cores per socket) validated up to 2933 MT/s. Max per DIMM: 64 GB RDIMM (2R), 128 GB LRDIMM. Max DRAM up to 6 TB with 48x 128 GB LRDIMM. Optional Intel Optane DC persistent memory (up to 24 PMem); up to 15.36 TB max combined PMem and LRDIMM. Validated DDR4 DIMM speeds 2666 and 2933 MT/s (configuration-dependent).

Confirmed = listed in the vendor's memory documentation for this server. Vendor match = the vendor's own part cross-reference matches the module and its speed is validated for the platform; not taken from this server's memory list. Spec match = meets this platform's JEDEC requirements (generation, form factor, validated speed); interchangeability is spec-based, not per-server testing. How we verify →