$166.78In Stock — Usually Ships in 1–3 Business Days
About the 647889-B21
This Compaq 647889-B21 delivers Server Memory functionality and is built for 24/7 enterprise duty cycles. Technical specifications include capacity of 8 GB, pc standard of PC3-12800, number of sticks of 1, frequency of 1600 MHz, connector of 240-pin, memory class of ECC, Registered, features of Dual-Rank. Workload fit covers virtual desktop infrastructure (Citrix, VMware Horizon), Java application servers (Tomcat, JBoss, WebLogic), enterprise data warehouse (Teradata, Vertica), and Hadoop/Spark cluster compute. Pro Disk Network supplies the 647889-B21 to US business buyers. Stocked units ship in 1–3 business days. Pro Disk Network applies a 90-day functional warranty. Free US ground shipping on orders over $150.
The 647889-B21 is a Compaq server memory component with capacity 8 GB, pc standard PC3-12800, number of sticks 1. Pro Disk Network sells the 647889-B21 for $166.78 with US shipping in 1–3 business days and a 30-day return guarantee.
Reviewed By
Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the 647889-B21 are shown on this page.
Trust Signals
US-based LLC — 7345 W Sand Lake Rd, STE 210, Office 3208, Orlando, FL 32819
US Shipping in 1–3 Business Days — in-stock orders ship via UPS
30-Day Returns — pre-paid label on DOA and defective items
Quick Answer: What servers is the 647889-B21 compatible with?
The 647889-B21 is a Compaq server 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 647889-B21 ship?
Pro Disk Network usually dispatches the 647889-B21 in 1–3 business days. 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 647889-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.
What is the 647889-B21?
The 647889-B21 is a Compaq server memory module with capacity 8 GB and pc standard PC3-12800, manufactured by Compaq. Pro Disk Network ships this part new and certified-refurbished from our US warehouse with dispatch in 1–3 business days, backed by a 30-day return guarantee.
Pros & Cons of 647889-B21
Pros
RDIMM / LRDIMM clearly labelled for population-rule clarity
Cons
Not for laptop SO-DIMM upgrades — server DIMM only
LRDIMM and RDIMM are not interchangeable
Original retail box not always included on refurbished tier
Frequently Asked Questions about 647889-B21
Is the 647889-B21 a genuine Compaq part?
Yes. Pro Disk Network sources every 647889-B21 as factory-original Compaq inventory. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned Compaq servers, surface-tested, and re-warranted by Pro Disk Network for 90 days.
What servers is the 647889-B21 compatible with?
The 647889-B21 is a Compaq server 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 647889-B21 ship?
Pro Disk Network usually dispatches the 647889-B21 in 1–3 business days. 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 647889-B21?
New 647889-B21 units carry the full Compaq manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (90 days refurbished). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the 647889-B21?
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 647889-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 Compaq manufacturer warranty and command a 20-30% premium over bulk-OEM tier. New (bulk-OEM) units are factory-fresh modules sold without retail box. Refurbished units come from decommissioned servers, are individually MemTest-validated, and carry a 90-day advance-replacement warranty.