This item, 840758-091, is the HPE assembly number for the product described as 32GB (1x32GB) Dual Rank x4 DDR4-2666 CAS-19-19-19 Registered Smart Memory Kit. Further details below.
Expand your HPE ProLiant Gen10 server with the 840758-091 32GB (1x32GB) Dual Rank x4 DDR4-2666 Registered Smart Memory Kit. This 288-pin DDR4 SDRAM DIMM runs at 2666 MHz (PC4-21300) with CAS Latency CL19 (19-19-19) timings and a low 1.2V supply voltage, delivering high-capacity performance for virtualization, databases, and demanding workloads without driving up power draw. Registered (RDIMM) architecture and ECC data integrity checking help keep memory-intensive applications stable and error-free around the clock.
As genuine HPE Smart Memory, the 840758-091 module is qualified for HPE Gen10 platforms with 1st generation CPUs, including the BL460c, DL360, DL380, DL560, DL580, ML110, ML350, XL170r, and XL190r Gen10 servers. With a 4096 x 72 module configuration and x4 chip organization, it's an easy, drop-in way to scale capacity to 32GB per slot. Global One Technology backs every module with quantity discounts and fast shipping.
HPE Option Part #: 815100-B21
HPE Spare Part #: 850881-001
HPE Assembly Part #: 840758-091
PRODUCT SPECIFICATIONS FOR 840758-091:
- Type: DRAM
- Product Type: Memory module
- Form Factor: DIMM 288-pin
- Technology: DDR4 SDRAM
- Storage Capacity: 32 GB
- Registered or Buffered: Registered
- Data Integrity Check: ECC
- Module Configuration: 4096 x 72
- Chips Organization: X4
- Memory Speed: 2666 megahertz
- Memory Specification Compliance: PC4-21300
- Supply Voltage: 1.2 volt
- CAS Latency: CL19
- Latency Timings: 19-19-19
- RAM Features: Dual Rank
RESOURCES FOR 840758-091 (815100-B21)
Quickspecs for 815100-B21COMPATIBLE WITH:
PROLIANT BL SERIES
PROLIANT DL SERIES
PROLIANT ML SERIES
PROLIANT XL SERIES
** This list may not be complete. Contact us via Live Chat if you have any questions about compatibility.
FREQUENTLY ASKED QUESTIONS FOR 840758-091:
- Which servers is the 840758-091 memory module compatible with?
The 840758-091 32GB DDR4-2666 Registered Smart Memory module is compatible with HPE Gen10 servers using 1st generation CPUs, including the BL460c Gen10, DL360 Gen10, DL380 Gen10, DL560 Gen10, DL580 Gen10, ML110 Gen10, ML350 Gen10, XL170r Gen10, and XL190r Gen10. - Is the 840758-091 registered ECC memory?
Yes. The 840758-091 is a Registered (RDIMM) DDR4 module with ECC data integrity checking, which helps detect and correct memory errors for greater stability in mission-critical server workloads. - What are the speed and latency specs of the 840758-091?
The 840758-091 is a 32GB dual rank x4 DDR4 SDRAM DIMM rated at 2666 MHz (PC4-21300) with CAS latency CL19 and 19-19-19 timings, operating at 1.2V in a 288-pin DIMM form factor.
HPE PARTSURFER INFO FOR 840758-091 (815100-B21)
| Spare PN | Description | |
|---|---|---|
 | 850881-001 | 32GB PC4-2666V-R, registered Synchronous Dynamic Random Access Memory (SDRAM) 2Gx4, operated in a Dual Data Rate (DDR4) mode, packaged in a dual in-line memory module organized as 4Gx72 ; |
Last Updated: 2026-09-03
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This product is warrantied against hardware failure for a period of 5 Years from the date of purchase. Before making a purchase, please take a moment to review our return policy below.
Returns
It is the customer's responsibility to verify compatibility with their machine(s) before placing an order. If an item is ordered by mistake, it can be returned for refund, minus a 25% restocking fee, within 5 business days of receipt. The cost of freight is not refundable.
Please be aware that factory-sealed equipment can only be returned if it remains unopened.
Defective Products
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In case your hardware becomes defective during the Global One warranty period, but the HPE warranty has expired, you can return the product to us for a working replacement. You are responsible for the shipment of returned merchandise. However, we will cover the expense of Ground /Economy shipment for the replacement item(s).
Requesting an RMA
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