64 GB DDR4-2666 ECC Load-Reduced DIMM (LRDIMM), quad-rank ×4. Sold by HPE, Dell, Lenovo and Cisco under their own part numbers, all cross-referenced below.
OEM cross-references are compiled from distributor cross-reference data and OEM documentation. Verify against your vendor's parts list before ordering.
Spec match covers every DDR4 LRDIMM platform we track, so the spec-match rows above are a sample across vendors: 24 further platforms also match this module on spec. A server missing from this table is not a compatibility limit. Browse all servers →
Confirmed = listed in the vendor's memory documentation for that server. Vendor match = the vendor's own part cross-reference matches this module and its speed is validated for the platform; the module is not taken from that server's memory list. Spec match = this module meets the platform's JEDEC requirements (generation, form factor, validated speed); interchangeability is spec-based, not per-server testing. Confirm against your server's qualified parts list before ordering.
Compatible alternatives any brand · same JEDEC specification
Modules match on all key specifications (type, form factor, capacity, speed, rank organization) and are generally interchangeable in servers that accept this spec.
Interchangeability is based on matching JEDEC specifications, not per-server testing. Confirm against your server vendor's qualified parts list.View the full family →
Frequently asked
Is HPE 815101-B21 the same module as M386A8K40BM2-CTD?
Yes. HPE resells this Samsung module under part number 815101-B21; HPE does the same as 840759-091, HPE does the same as 850882-001, HPE does the same as 838085-B21, HPE does the same as 840759-191, HPE does the same as 868844-001, Dell does the same as SNP4JMGMC/64G, Lenovo does the same as 7X77A01305, Lenovo does the same as 01DE975, Cisco does the same as 15-105084-01. The physical module is identical: OEM part numbers are branding, not different hardware.
Can I use a Kingston or Micron module instead?
In most servers, yes: KSM26LQ4/64HAI (Kingston), KSM26LQ4/64HAM (Kingston), KSM26LQ4/64HCI (Kingston) match this module on every key specification (64 GB, DDR4-2666, LRDIMM, 4Rx4). Keep vendors consistent within a memory bank, and check your server's qualified parts list for edge cases.
What servers take M386A8K40BM2-CTD?
Cisco UCS B200 M5, Cisco UCS B200 M6, Cisco UCS C220 M5, Cisco UCS C220 M6, among others, match it through the vendor's own part cross-reference (e.g. HPE 815101-B21) with a validated speed. Other DDR4 LRDIMM platforms generally accept it too; verify against the server's qualified parts list.
