HPE INT Xeon-g 5418N CPU for HPE OEM - P61454-B21

HPE P61454-B21 Xeon Gold 5418N 24-Core Server Processor

Overview

The HPE P61454-B21 is an OEM-integrated Intel Xeon Gold 5418N server processor built on the Sapphire Rapids microarchitecture. Engineered for dual-socket HPE server platforms, it delivers 24 physical cores with simultaneous multithreading for 48 logical threads — the right density for compute-heavy workloads that demand sustained throughput without hitting the thermal ceiling of higher-wattage parts. At a 165W TDP, it sits in the efficiency tier of the Scalable processor lineup, making it a deliberate fit for environments where rack power and cooling headroom are constrained but compute requirements remain substantial. If you're evaluating processors for a new HPE server build or a socket-for-socket upgrade, P61454-B21 (often searched as P61454 B21) is the OEM-qualified part number to order.

Key Features

• 24 Cores / 48 Threads at 1.80 GHz Base, 3.80 GHz Turbo: The 2.0 GHz spread between base and turbo means lightly threaded tasks burst hard while fully loaded workloads still sustain 1.8 GHz across all 24 cores. For analytics-heavy server applications — AI inference, video processing pipelines, or dense VM consolidation — this range gives the scheduler room to prioritize latency-sensitive threads without starving background jobs.
• 45 MB L3 Cache: A large last-level cache reduces DRAM fetches for working-set-heavy workloads like in-memory databases, video analytics buffers, or containerized microservices. Less data spilling to DDR5 means lower effective latency on cache-resident data paths.
• DDR5-4400 MT/s with 8 Memory Channels, up to 4 TB: Eight memory channels running at 4400 MT/s provide substantial aggregate bandwidth. Supporting up to 4 TB per socket (per HPE OEM spec) means this processor can anchor large in-memory analytics or virtualization hosts without hitting a memory ceiling mid-deployment. Note: this requires DDR5 DIMMs at 2DPC (2 DIMMs per channel) configuration to reach rated speed.
• PCIe 5.0 with 80 Lanes: PCIe Gen 5 doubles the per-lane bandwidth over Gen 4. With 80 lanes available, the platform can simultaneously support high-bandwidth NVMe storage, 100GbE+ networking, and GPU/accelerator cards without lane-sharing compromises. For AI compute nodes or high-throughput storage servers, this matters more than the core count.
• 3 UPI Links: Three Ultra Path Interconnect links support direct die-to-die communication in 2-socket configurations. Three UPI links provide more coherency bandwidth than dual-UPI alternatives — relevant when both sockets are running memory-intensive workloads and NUMA cross-traffic is expected.
• Intel AMX + AVX-512 with 2 FMA Units: Advanced Matrix Extensions (AMX) accelerate INT8 and BF16 matrix operations in silicon, enabling on-CPU AI inference without requiring a discrete accelerator. Paired with two AVX-512 FMA units for vector workloads, this makes the 5418N a credible fit for edge AI inference or moderate ML inferencing tasks baked into the server itself.
• 165W Thermal Design Power: At 165W, this processor draws less than the higher-core-count Sapphire Rapids variants. That directly reduces per-socket cooling requirements and rack-level power draw — a real factor in dense deployments where PDU capacity and heat dissipation are design constraints.
• FCLGA4677 Socket, 77.5 × 56.5 mm Package: Designed for HPE server platforms using the FCLGA4677 socket with Sapphire Rapids support. Verify your specific HPE server model's processor compatibility matrix before ordering — not all FCLGA4677 boards support the same TDP range or SKU binning.

Integration & Compatibility

The P61454-B21 is an HPE OEM processor, meaning it is validated and shipped as part of HPE's server integration supply chain rather than as a retail boxed Intel part. It carries HPE's OEM qualification for supported ProLiant and Synergy platforms that accept FCLGA4677 Sapphire Rapids processors. The S3 core stepping is the production-stable revision for this family. Memory compatibility requires DDR5 ECC registered DIMMs; the rated 4400 MT/s speed at 2DPC should be validated against the specific server's memory qualification list (MQL) since achievable speed depends on DIMM count, rank, and platform BIOS configuration. PCIe 5.0 connectivity is available through supported HPE platform I/O infrastructure — the processor's 80 lanes are the ceiling, but actual lane allocation depends on the server's PCIe topology and riser configuration.

Frequently Asked Questions

Q: What socket does the P61454-B21 use, and is it compatible with all HPE FCLGA4677 servers?

A: The P61454-B21 uses the FCLGA4677 socket. However, not every HPE server with this socket supports every Sapphire Rapids SKU — TDP limits and BIOS qualification can vary by platform. Verify your specific HPE server model's processor compatibility list before ordering.

Q: Does the P61454-B21 support DDR4 memory?

A: No. The Xeon Gold 5418N on the Sapphire Rapids platform requires DDR5 ECC registered DIMMs. DDR4 is not compatible with this processor generation or its FCLGA4677 socket.

Q: What is the difference between the P61454-B21 OEM part and a standard Intel boxed Xeon 5418N?

A: The P61454-B21 is an HPE OEM-qualified part, sourced and validated by HPE for integration into their server platforms. It may carry HPE-specific firmware and warranty terms tied to the host server rather than a standalone Intel retail warranty. Use the HPE part number when ordering for HPE server platforms to ensure support entitlement.

Q: Does the P61454-B21 support Intel AMX for AI inference workloads?

A: Yes. The Xeon Gold 5418N includes Intel Advanced Matrix Extensions (AMX), which accelerate INT8 and BF16 matrix math in hardware — supporting on-CPU AI inference without requiring a discrete GPU or accelerator card.

Q: How many memory channels does the P61454-B21 support, and what is the maximum memory capacity?

A: The processor supports 8 memory channels with DDR5-4400 MT/s at 2DPC, with a maximum supported memory capacity of 4 TB per socket.

Q: What PCIe generation does the P61454-B21 support?

A: The processor supports PCIe 5.0 with up to 80 lanes — doubling per-lane bandwidth compared to PCIe 4.0, which benefits high-throughput NVMe, 100GbE networking, and GPU/accelerator cards deployed in the same server.

Ted Perry

The P61454-B21 is a deliberate engineering choice, not a default one. The 165W TDP is the detail that shapes the deployment — you're getting 24 Sapphire Rapids cores with AMX and PCIe 5.0 at a power envelope that fits standard HPE dual-socket configurations without requiring upgraded cooling or PDU circuits. That's a meaningful constraint removed from the planning process on dense rack builds.

Technical Highlights:

• 1.80–3.80 GHz Turbo Range: The 2.0 GHz burst headroom means latency-sensitive tasks — query engines, API services, real-time inference — get the full 3.80 GHz when the scheduler has headroom, while sustained 24-core workloads settle at 1.80 GHz without throttling.
• 8-Channel DDR5-4400 at 4 TB Max: Eight DDR5 channels at 4400 MT/s deliver substantially higher memory bandwidth than DDR4 predecessors — critical for in-memory analytics or large VM footprints. The 4 TB ceiling means this socket can hold its own as a memory-dense node without adding a second server.
• Intel AMX + 2 AVX-512 FMA Units: AMX brings matrix acceleration into the CPU itself, enabling BF16 and INT8 inference workloads without adding a GPU to the BOM. For moderate AI inferencing baked into an application server — not a dedicated AI training rig — this is the right trade-off.

Deployment Considerations:

• DDR5 at 2DPC to hit rated 4400 MT/s speed: single DIMM per channel will run at lower transfer rates. Plan your DIMM population strategy against the HPE server's memory qualification list before finalizing the memory BOM.
• This is an HPE OEM part — warranty and support entitlement flow through the host server's HPE support contract, not a standalone Intel warranty. Don't substitute the retail Xeon 5418N and expect equivalent HPE platform support coverage.

The right platform for this processor is a power-constrained dual-socket HPE server running mixed workloads — virtualization hosts with AI inference services, analytics nodes that can't justify a discrete accelerator, or dense application servers where the 165W budget is a hard design constraint rather than just a preference.