P51181-B21 - HPE BCM 5719 1GB 4P BASE-T OCP3 Network Adapter

HPE P51181-B21 — Broadcom 5719 1GbE 4-Port BASE-T OCP3 Network Adapter

What it is

P51181-B21 is an HPE enterprise Ethernet network adapter designed for HPE ProLiant servers.
It’s a 4-port 1GbE BASE-T adapter based on the Broadcom BCM5719 controller in the OCP 3.0 form factor, delivering reliable, dual-redundant server networking for general-purpose and business workloads.

Why buyers pick P51181-B21 (plain English)

Four ports for flexible connectivity
Multiple 1Gb links support link aggregation, failover, or network segmentation without additional hardware.

OCP 3.0 form factor
Fits in the dedicated OCP slot, freeing up PCIe slots for storage, GPUs, or accelerators.

Proven Broadcom silicon
BCM5719 delivers stable, low-latency performance with mature driver support.

Perfect for classic networking
Ideal for standard Ethernet uplinks, management networks, and broad compatibility.

HPE-qualified reliability
Firmware and driver validation with ProLiant servers ensures smooth deployment and support.

60-second spec box (P51181-B21)

Adapter type
Ethernet network adapter

Ports
4 × 1GbE BASE-T

Speed
1GbE

Controller
Broadcom BCM5719

Form factor
OCP 3.0

Host interface
OCP slot

Media supported
Copper Ethernet (RJ-45)

Platform
HPE ProLiant servers with OCP 3.0 support

Use case
General-purpose server networking, management VLANs, and redundant 1GbE uplinks.

Where it fits (and when to choose something else)

Perfect for:

• ProLiant servers with OCP 3.0 slots

• Redundant or aggregated 1Gb uplinks

• Management, backup, or VM traffic

• Environments where 1Gb connectivity suffices

Choose something else if:

• You need higher speeds → 10G or 25G adapters

• You need SFP+ optics → fiber NICs

• You need copper PoE → PoE-capable adapters

TL;DR

P51181-B21 is HPE’s 4-port 1GbE BASE-T OCP3 adapter with Broadcom BCM5719:
a reliable, server-validated network card providing flexible 1Gb connectivity while preserving PCIe slots.

• Quad-port connectivity: Provides four 1Gb Ethernet ports, offering flexible network segmentation and higher density.
• Energy efficient: With a low operational power consumption of 4.69 Watts, it helps reduce data center energy costs.
• Virtualization support: Includes features like Receive Side Scaling (RSS) to help optimize performance in virtualized server environments.
• OCP 3.0 standard: The standardized OCP 3.0 form factor ensures simplified installation and maintenance in compatible HPE server models.