$155.79In Stock — Usually Ships in 1–3 Business Days
About the 518855-L21
This HP 518855-L21 delivers AMD Unboxed Processors functionality and is built for 24/7 enterprise duty cycles. Technical specifications include clock speed of 2.4 GHz, cache of 12MB L3, generation of Gen34. Common deployment scenarios include in-place server upgrades from prior Xeon/EPYC generations, matched-pair second-socket installation, hot-spare provisioning, and refurbished rebuild programs for older platforms. Pro Disk Network maintains the 518855-L21 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 90-day Pro Disk Network functional warranty. Dispatch in 1–3 business days; free standard ground shipping on US orders over $150.
The 518855-L21 is a HP amd unboxed processors component with clock speed 2.4 GHz, cache 12MB L3, generation Gen34. Pro Disk Network sells the 518855-L21 for $155.79 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 518855-L21 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 socket does the 518855-L21 use?
Confirm the socket against your motherboard's CPU support list - Intel Xeon Scalable spans LGA 3647 (1st/2nd gen), LGA 4189 (3rd gen Ice Lake), and LGA 4677 (4th/5th gen Sapphire/Emerald Rapids). A BIOS update is often required for newer steppings even on the same socket. Email sales@prodisknetwork.com with your motherboard model for a compatibility check.
How fast does the 518855-L21 ship?
518855-L21 orders ship in 1–3 business days from US warehouses. Delivery is next business day to most metro ZIPs via FedEx/UPS overnight; ground delivery covers remaining US in 1-4 business days.
The 518855-L21 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 Datacenter licenses by core, but Hyper-V scales linearly. Higher-clock, mid-core SKUs win for transactional workloads.
Citrix VDI Pool — Frequency-sensitive — prefer high-clock 16–18 core SKUs over high-core-count parts to maintain user-perceived snappiness.
Kubernetes / Tanzu Workers — Higher core count amortises better across many small Pods. EVC mode planning matters for live-migrate parity.
AI Inference Host — Sapphire Rapids and Emerald Rapids include AMX silicon for INT8 inference acceleration — meaningful uplift for BERT, ResNet, and LLM serving.
What is the 518855-L21?
The 518855-L21 is a HP server-class processor with clock speed 2.4 GHz and cache 12MB L3, manufactured by HP. 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 518855-L21
Pros
Lower cost than the manufacturer channel for refresh cycles
Matched-pair option for dual-socket consistency
Sequential serial numbers on bulk orders for cluster builds
Cons
Refurbished tier may have minor IHS markings
Tray packaging — no retail Intel/AMD cooler included
Frequently Asked Questions about 518855-L21
Is the 518855-L21 a genuine HP part?
Yes. Pro Disk Network sources every 518855-L21 as factory-original HP inventory. 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 90 days.
What socket does the 518855-L21 use?
Confirm the socket against your motherboard's CPU support list - Intel Xeon Scalable spans LGA 3647 (1st/2nd gen), LGA 4189 (3rd gen Ice Lake), and LGA 4677 (4th/5th gen Sapphire/Emerald Rapids). A BIOS update is often required for newer steppings even on the same socket. Email sales@prodisknetwork.com with your motherboard model for a compatibility check.
How fast does the 518855-L21 ship?
518855-L21 orders ship in 1–3 business days from US warehouses. Delivery is next business day to most metro ZIPs via FedEx/UPS overnight; ground delivery covers remaining US in 1-4 business days.
What is the warranty on the 518855-L21?
New 518855-L21 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 (90 days refurbished). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the 518855-L21?
Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
Pro Disk Network Buyer’s Guide: AMD Unboxed Processors
Socket Compatibility, EVC Mode, and BIOS Revision Planning
For VMware vSphere clusters, EVC (Enhanced vMotion Compatibility) mode dictates which CPU generations can coexist in the same cluster while still supporting live migration. Adding a newer-generation 518855-L21 to a cluster with older CPUs requires setting EVC to the older baseline, which disables newer instructions on the new CPU. Plan EVC mode at cluster creation time; changing it later requires powering off the cluster.
AI Workloads, AMX, and the Inference Performance Story
Plan memory bandwidth alongside the CPU: AMX inference is memory-bandwidth sensitive. A 518855-L21 paired with insufficient memory channels (e.g., DDR5-4800 in fewer than 8 channels per socket) will underperform its theoretical peak by 30-40%. Confirm motherboard channel count and DIMM population before ordering.