$86.38In Stock — Usually Ships in 1–3 Business Days
About the 371-3951
Sourced for enterprise IT teams, the Sun 371-3951 (371-3951 - Sun 2.5GHz 1333MHz FSB 12MB L2 Cache Socket LGA771 Intel Xeon L5420 4-Core Processor) is a Intel Unboxed Processors component appropriate for new-build, expansion, or warranty-replacement procurement. Technical specifications include clock speed of 2.5 GHz, bus speed of 1333 MHz FSB, cache of 12MB L2, socket of LGA771. 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 371-3951 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 371-3951 is a Sun intel unboxed processors component with clock speed 2.5 GHz, bus speed 1333 MHz FSB, cache 12MB L2. Pro Disk Network sells the 371-3951 for $86.38 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 371-3951 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
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 371-3951 ship?
If in stock, the 371-3951 ships in 1–3 business days. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and pallet orders may need extra handling time; we confirm the ship date with your order.
The 371-3951 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.
VMware vSphere ESXi 8 Host — Per-CPU core count drives VVF/VCF licensing cost — choose 16–24 cores for cost-optimal density unless workload is core-bound.
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.
What is the 371-3951?
The 371-3951 is a Sun server-class processor with clock speed 2.5 GHz and bus speed 1333 MHz FSB, manufactured by Sun. 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 371-3951
Pros
Shipping in 1–3 business days from our US warehouse cuts deployment lead time
Cons
Older socket family — confirm motherboard compatibility
BIOS update typically required for newer CPU steppings
Not a fit for desktop platforms — these are server SKUs
Frequently Asked Questions about 371-3951
Is the 371-3951 a genuine Sun part?
Yes. Pro Disk Network sources every 371-3951 as factory-original Sun inventory. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned Sun servers, surface-tested, and re-warranted by Pro Disk Network for 90 days.
What socket does the 371-3951 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 371-3951 ship?
If in stock, the 371-3951 ships in 1–3 business days. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and pallet orders may need extra handling time; we confirm the ship date with your order.
What is the warranty on the 371-3951?
New 371-3951 units carry the full Sun 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 371-3951?
Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
371-3991 — 371-3991 - Sun 4-Port SAS 3GB/s PCI-Express Internal Host Bus Adapter — $121.05
371-3991-01 — 371-3991-01 - Sun 4-Port SAS 3GB/s PCI-Express Host Bus Adapter — $226.08
371-3992 — 371-3992 - Sun Fan Tray Assembly RoHS-Y — $163.16
Pro Disk Network Buyer’s Guide: Intel Unboxed Processors
Socket Compatibility, EVC Mode, and BIOS Revision Planning
Choosing the 371-3951 for a server upgrade or replacement starts with socket compatibility. CPU sockets are tied to motherboard chipsets and revisions; a board that supports Skylake-SP may or may not support Cascade Lake-SP depending on BIOS. Before ordering, look up the motherboard QVL (qualified vendor list) and confirm the 371-3951 appears with a supported BIOS version. If the BIOS needs an update, plan the flash before swapping CPUs — many systems will not POST long enough to flash with the wrong CPU installed.
AI Workloads, AMX, and the Inference Performance Story
For dedicated AI inference hosts, prioritize core count over clock speed. INT8 inference is bandwidth-bound, not frequency-bound, so a 32-core part at 2.5 GHz outperforms a 16-core part at 3.5 GHz on most LLM workloads. For mixed virtualisation + occasional inference workloads, prioritize clock speed — VDI and OLTP database workloads benefit from the higher frequency.