HP 64GB 2666MHz DDR4 PC4-21300 ECC Registered CL19 288-Pin Load Reduced DIMM 1.2V Quad Rank x4 Memory Module – 840759-091

HPE 840759-091 64GB DDR4-2666 ECC LRDIMM — 4Rx4 CL19 Server Memory

The HPE 840759-091 is a 64GB DDR4-2666 ECC Load Reduced DIMM providing quad-rank x4 server memory for HPE ProLiant Gen10 servers — delivering CL19 latency at 2666MHz (PC4-21300) with 1.2V operation and LRDIMM load reduction for high-density 64GB per-slot server memory in HPE multi-socket platforms.

Key Features

• 64GB DDR4-2666 ECC LRDIMM — 4Rx4 CL19 for optimal LRDIMM latency at 64GB density
• CL19 latency — lowest latency 64GB DDR4-2666 LRDIMM variant for HPE ProLiant Gen10
• LRDIMM load reduction enabling quad-rank 64GB per slot without exceeding channel loading limits
• 1.2V low-voltage operation for energy-efficient high-density server memory
• HPE-certified for ProLiant Gen10 LRDIMM platforms

Product Specifications

• Part Number: 840759-091
• Manufacturer: HP / HPE
• Capacity: 64GB
• Type: DDR4 ECC Load Reduced DIMM (LRDIMM)
• Speed: 2666MHz (PC4-21300)
• CAS Latency: CL19
• Voltage: 1.2V
• Ranks x Width: 4Rx4
• Pins: 288-Pin

Memory Specifications

• ECC: Yes — ECC Load Reduced (LRDIMM)
• Form Factor: DIMM (288-pin, full-height)
• Error Correction: SECDED ECC with LRDIMM data buffer
• Memory Standard: PC4-21300 (DDR4-2666)

Performance Specifications

• Bandwidth: Up to 21,333 MB/s theoretical peak
• ECC Type: SECDED with LRDIMM 4-rank data buffer abstraction
• RAS Features: ECC, memory mirroring, rank sparing (platform dependent)

Use Cases

• 64GB CL19 LRDIMM for maximum DDR4-2666 performance at high memory density in HPE Gen10
• In-memory database, SAP HANA, and large virtualization workloads on HPE ProLiant Gen10
• Preferred CL19 variant over 850882-001 (CL22) where lowest LRDIMM latency is prioritized
• Replacing failed 64GB LRDIMM modules in HPE ProLiant Gen10 deployments

Compatibility

• HPE ProLiant Gen10 servers supporting DDR4 LRDIMM: DL360, DL380, DL560, DL580 Gen10
• Requires LRDIMM-capable DIMM slots — cannot be mixed with RDIMM modules
• CL19 variant — preferred over CL22 for latency-sensitive server workloads
• Verify HPE memory population guide per server model before installation

Frequently Asked Questions

What is the difference between 840759-091 and 850882-001?

Both are 64GB DDR4-2666 ECC 4Rx4 LRDIMMs for HPE ProLiant Gen10, differing in CAS latency — 840759-091 is CL19 (lower latency, preferred) while 850882-001 is CL22. For latency-sensitive workloads, the CL19 variant (840759-091) is recommended when available.

What is the difference between 840759-091 and P06182-001?

Both are 64GB DDR4-2666 ECC 4Rx4 CL19 LRDIMMs for HPE ProLiant Gen10 — they are functionally equivalent with identical specifications. The 840759-091 uses the HPE OEM (-091) suffix, while P06182-001 uses the P-series part number format. Both are interchangeable in supported HPE Gen10 servers.

Does the 840759-091 require a specific BIOS version on HPE Gen10 servers?

HPE periodically releases BIOS and firmware updates that extend memory compatibility. For 64GB LRDIMM modules, ensure your HPE server is running a recent BIOS version as listed in HPE”s memory compatibility advisory for your specific server model and processor combination.

The HPE 840759-091 delivers 64GB DDR4-2666 ECC LRDIMM capacity at CL19 latency in a 4Rx4 configuration — providing the preferred low-latency 64GB LRDIMM option for HPE ProLiant Gen10 server platforms requiring high-density DDR4 memory with optimal LRDIMM performance for in-memory database and large-scale virtualization workloads.