HPE 32GB DDR5-6400 EC8 Registered DIMM 2Rx8 — P64985-B21

The HPE P64985-B21 is a 32GB DDR5-6400 (PC5-51200) EC8 Registered DIMM in dual-rank 2Rx8 configuration and is the standard option kit for HPE ProLiant Gen11 servers. EC8 (Enhanced Correction 8) delivers advanced multi-bit error correction at DDR5-6400 maximum frequency, providing stronger data integrity for mission-critical enterprise workloads on Intel Xeon Scalable 5th Generation (Emerald Rapids) platforms.

Key Features

• 32GB DDR5-6400 EC8 RDIMM 2Rx8 option kit — enhanced ECC at maximum DDR5 frequency for Gen11
• EC8 multi-bit error correction for stronger data integrity beyond standard DDR5 ECC at DDR5-6400
• 6400MHz (PC5-51200) for ~102.4 GB/s peak bandwidth on Xeon Scalable 5th Gen Gen11 platforms
• 2Rx8 dual-rank at 1.1V — 32GB capacity per slot with EC8 protection for Gen11 deployments

Product Specifications

• Part Number: P64985-B21
• Manufacturer: HPE
• Capacity: 32GB
• Type: DDR5 EC8 Registered (RDIMM)
• Speed: 6400MHz (PC5-51200)
• Voltage: 1.1V
• Ranks x Width: 2Rx8
• Pins: 288-pin

Memory Specifications

• Memory Standard: JEDEC DDR5-6400
• Error Correction: EC8 — enhanced multi-bit error correction beyond standard DDR5 ECC
• Buffer Type: Registered (RDIMM)
• DRAM Generation: DDR5

Performance Specifications

• Peak Bandwidth: ~102.4 GB/s (PC5-51200) at DDR5-6400 frequency
• ECC Type: EC8 — advanced multi-bit correction for mission-critical data integrity
• RAS Features: Post-package repair, patrol scrubbing, advanced error recovery (platform dependent)

Use Cases

• Standard option kit for Gen11 32GB DDR5-6400 EC8 RDIMM mission-critical memory builds
• Financial, healthcare, and government workloads requiring EC8 enhanced ECC at DDR5-6400
• High-frequency 32GB per slot DDR5-6400 configurations on Emerald Rapids Gen11 platforms
• AI/ML and HPC workloads requiring maximum DDR5-6400 bandwidth with EC8 data integrity

Compatibility

• HPE ProLiant DL380/DL360/DL560 Gen11 supporting EC8 DDR5-6400 memory
• HPE ProLiant ML350 Gen11 and EC8-capable DDR5-6400 Gen11 platforms
• Intel Xeon Scalable 5th Generation (Emerald Rapids) natively supporting DDR5-6400

Frequently Asked Questions

What is the difference between 2Rx8 and 2Rx4 at 32GB DDR5-6400?

2Rx8 uses x8-width DRAM devices across two ranks, while 2Rx4 uses x4-width devices. At 32GB, 2Rx8 typically uses 16Gb DRAM die vs. 8Gb die in 2Rx4. Platform population rules may differ between 2Rx8 and 2Rx4 — consult HPE ProLiant Gen11 QuickSpecs for maximum DIMM population with each rank/width configuration.

Is P64985-B21 interchangeable with 64GB DDR5-6400 EC8 RDIMMs like P69728-B21?

No — P64985-B21 is 32GB DDR5-6400 2Rx8 EC8 RDIMM, while P69728-B21 is 64GB DDR5-6400 2Rx4 EC8 RDIMM. Capacity and rank/width differ — they are not interchangeable. Use P64985-B21 for 32GB per slot configurations and P69728-B21 for 64GB per slot maximum density.

Can EC8 DDR5-6400 RDIMMs be mixed with standard ECC DDR5-6400 RDIMMs in Gen11?

Mixing EC8 and standard ECC DDR5 modules is generally not recommended and may not be supported. Consult HPE ProLiant Gen11 QuickSpecs for EC8 vs. standard ECC population rules. Use consistent EC8 modules across all slots in a memory channel for validated operation.

The HPE P64985-B21 32GB DDR5-6400 EC8 RDIMM 2Rx8 option kit delivers maximum-frequency DDR5 with enhanced multi-bit ECC for HPE ProLiant Gen11 mission-critical deployments. Order today — in stock at the lowest price.