HP part number 879505-B21 identifies the 879505-B21 - HP 8GB DDR4-2666MHz PC4-21300 ECC Unbuffered CL19 288-Pin DIMM Single Rank 1.2V Memory Module, an enterprise-grade Memory unit appropriate for data-center, server-room, and workstation deployment. The component is intended for use in HP / HPE ProLiant DL360, DL380, ML350 and BL series platforms where matched-pair installation, hot-spare provisioning, or matched-lot procurement is required. Technical specifications include capacity of 8 GB, pc standard of PC4-21300, connector of 288-pin, voltage of 1.2V, memory class of ECC, Unbuffered, features of Single-Rank. Typical workloads include VMware vSphere VM host memory, Kubernetes worker-node memory pool, in-memory database (Redis, Memcached, SAP HANA), and SAS / Splunk analytic workloads requiring large RAM footprint. Pro Disk Network maintains the 879505-B21 in our enterprise inventory and verifies each unit against manufacturer datasheet specifications prior to listing. New stock ships factory-sealed where available; refurbished units are tested under load before dispatch and ship with a 30-day Pro Disk Network functional warranty. Net 30 terms are available for qualified business accounts. Same-day dispatch on in-stock orders placed before 3pm ET; free standard ground shipping on US orders over $150.
The 879505-B21 is a HP memory component with capacity 8 GB, pc standard PC4-21300, connector 288-pin. Pro Disk Network sells the 879505-B21 for $140.00 with same-day US shipping and a 30-day free return guarantee.
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Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the 879505-B21 verified against the manufacturer datasheet and our internal lab benchmarks.
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2,000+ B2B Customers — MSPs, government, education, enterprise IT
Quick Answer: What servers is the 879505-B21 compatible with?
The 879505-B21 is a HP memory module. Confirm DIMM rank, voltage, and speed against the target server's supported memory list before deployment - mixed configurations may downclock to the slowest installed module. For server-specific population diagrams, email sales@prodisknetwork.com with your server serial number.
How fast does the 879505-B21 ship?
Pro Disk Network dispatches the 879505-B21 same-day on orders confirmed before 2 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
The 879505-B21 is deployed by US enterprises, MSPs, government, and education customers across multiple infrastructure scenarios. Below are the most common deployment patterns Pro Disk Network sees in real-world orders.
Hyper-V Cluster Node — Windows Server 2019/2022 Hyper-V hosts with Storage Spaces Direct. Dynamic memory allocation makes higher-density DIMMs cost-effective.
AI / ML Training — PyTorch and TensorFlow workloads benefit from large host memory pools for dataset preprocessing and CPU-side feature engineering.
Tanzu / Kubernetes Workers — Worker node memory expansion for high-density container deployments. Plan for 8–16 GB per moderate Pod baseline.
New, Bulk, or Refurbished — Choosing Your Tier
Pro Disk Network offers the 879505-B21 across three procurement tiers. Each tier is fully functional and warranted; the choice comes down to budget, warranty length, and whether the deployment is production-critical or capacity-expansion.
Tier
Discount vs OEM List
Warranty
Best For
New (Sealed OEM)
25–40%
HP manufacturer warranty (1–5 yr)
Production-critical first-tier
New (Bulk OEM)
50–65%
3-year Pro Disk Network warranty
New cluster builds, secondary tier
Refurbished
75–85%
12-month advance replacement
Capacity expansion, lab, dev/test, EOL refresh
Bulk & Volume Pricing for 879505-B21
Ships from our Orlando, FL warehouse — same-day US dispatch on orders placed before 2pm ET. Net 30 terms available for verified businesses, government and education.
Volume discounts on the 879505-B21 are automatic at checkout. Net 30 terms available for verified businesses, government, and education. Email sales@prodisknetwork.com for orders above 100 units.
Quantity
Discount
Unit Price
1
0%
$140.00
5+
4%
$134.40
10+
8%
$128.80
25+
13%
$121.80
50+
18%
$114.80
100+
23%
$107.80
What is the 879505-B21?
The 879505-B21 is a HP server memory module with capacity 8 GB and pc standard PC4-21300, manufactured by HP. Pro Disk Network ships this part new and certified-refurbished from our US warehouse with same-day dispatch on orders placed before 3 PM ET, backed by a 30-day return guarantee.
Pros & Cons of 879505-B21
Pros
Recovery from no-POST errors when refreshing aging servers
Drop-in DDR4/DDR5 RDIMM choices across most enterprise sockets
Heat-spreader and tray packaging suitable for production install
Cons
Memory must match existing DIMM rank/density for channel balance
Higher density modules can drop overall channel speed
BIOS update may be required on older revisions
Frequently Asked Questions about 879505-B21
Is the 879505-B21 a genuine HP part?
Yes. Pro Disk Network sources every 879505-B21 as factory-original HP inventory verified against the manufacturer parts registry before listing. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned HP servers, surface-tested, and re-warranted by Pro Disk Network for 12 months.
What servers is the 879505-B21 compatible with?
The 879505-B21 is a HP memory module. Confirm DIMM rank, voltage, and speed against the target server's supported memory list before deployment - mixed configurations may downclock to the slowest installed module. For server-specific population diagrams, email sales@prodisknetwork.com with your server serial number.
How fast does the 879505-B21 ship?
Pro Disk Network dispatches the 879505-B21 same-day on orders confirmed before 2 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
What is the warranty on the 879505-B21?
New 879505-B21 units carry the full HP manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (12 months refurbished, 36 months new bulk). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the 879505-B21?
Yes. Pro Disk Network offers automatic volume discounts at 10, 25, 50, and 100+ unit tiers. Net 30 terms are available for verified businesses, government, and education buyers. Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
Compatibility: Rank, Density, and Channel Population Rules
Memory population order for Xeon Scalable is documented in the motherboard manual; the typical rule is to populate channels symmetrically across both CPU sockets and across all six channels per socket. For two-socket builds with eight DIMMs, populate the white slot first on each channel; for sixteen-DIMM builds, populate both slots on every channel. Asymmetric population leaves performance on the table.
Pricing Strategy: New, Bulk, or Refurbished
The 879505-B21 is available across three procurement tiers, and the choice is driven by criticality, warranty coverage, and budget. New (sealed OEM) units carry the full HP manufacturer warranty and command a 20-30% premium over bulk-OEM tier. New (bulk-OEM) units are factory-fresh modules sold without retail box; Pro Disk Network warranties them for 36 months. Refurbished units come from decommissioned servers, are individually MemTest-validated, and carry a 12-month advance-replacement warranty.