HPE 16GB 2666MHz DDR4 PC4-21300 ECC Registered CL19 288-Pin DIMM 1.2V Dual Rank x8 Memory Module – 835955-B21

HPE 16GB DDR4-2666 ECC Registered DIMM — 835955-B21

The HPE 835955-B21 is a 16GB DDR4-2666 (PC4-21300) ECC Registered DIMM in a dual-rank 2Rx8 configuration and is the standard option kit for HPE ProLiant Gen10 servers. Operating at 1.2V with CL19 latency across 288 pins, it delivers ECC-protected DDR4-2666 memory for entry-level and mid-range Gen10 server deployments.

Key Features

• 16GB DDR4-2666 RDIMM option kit — standard procurement for Gen10 ProLiant 16GB memory slots
• 2666MHz (PC4-21300) bandwidth validated for Intel Xeon Scalable Gen10 platforms
• 2Rx8 dual-rank layout for cost-effective 16GB per slot ECC server memory
• 1.2V low-voltage registered operation for energy-efficient ProLiant Gen10 deployment

Product Specifications

• Part Number: 835955-B21
• Manufacturer: HPE
• Capacity: 16GB
• Type: DDR4 ECC Registered (RDIMM)
• Speed: 2666MHz (PC4-21300)
• CAS Latency: CL19
• Voltage: 1.2V
• Ranks x Width: 2Rx8
• Pins: 288-pin

Memory Specifications

• Memory Standard: JEDEC DDR4-2666
• Error Correction: ECC (Error Correcting Code)
• Buffer Type: Registered (RDIMM)
• DRAM Generation: DDR4

Performance Specifications

• Peak Bandwidth: ~42.7 GB/s (PC4-21300)
• ECC Type: Single-bit error correction, multi-bit error detection
• RAS Features: Advanced ECC, rank sparing, memory mirroring (platform dependent)

Use Cases

• HPE ProLiant Gen10 16GB per slot memory option kit builds and upgrades
• Entry-level virtualization and application server deployments on Gen10 Xeon Scalable
• Cost-effective ECC server memory for ProLiant Gen10 edge and branch office servers
• Multi-socket Gen10 memory population starting at 16GB per slot

Compatibility

• HPE ProLiant DL360 Gen10, DL380 Gen10, DL180 Gen10
• HPE ProLiant ML350 Gen10, BL460c Gen10
• Intel Xeon Scalable 1st/2nd Generation (Skylake-SP / Cascade Lake-SP) supporting DDR4-2666

Frequently Asked Questions

Is 835955-B21 the same as 840756-091?

Yes — both are HPE 16GB DDR4-2666 2Rx8 ECC RDIMM modules with identical specifications. 835955-B21 is the option kit and 840756-091 is the factory/OEM configuration variant — they are fully interchangeable.

What is the difference between 835955-B21 (16GB 2Rx8) and 815100-B21 (32GB 2Rx4)?

835955-B21 is a 16GB 2Rx8 RDIMM suitable for entry-level Gen10 configurations. 815100-B21 is a 32GB 2Rx4 module offering twice the capacity per slot with a different DRAM layout. Choose based on per-slot capacity needs and total memory budget.

Can 835955-B21 be upgraded to 32GB later by replacing modules?

Yes — ProLiant Gen10 servers allow module replacement. Swapping 835955-B21 (16GB) with 815100-B21 (32GB) in the same slots doubles per-slot capacity, subject to server memory channel and population rules.

The HPE 835955-B21 16GB DDR4-2666 2Rx8 RDIMM is the option kit standard for entry-level and mid-range HPE ProLiant Gen10 server memory. Order today — in stock at the lowest price.