P42041-B21 is an HPE enterprise Ethernet network adapter designed for HPE ProLiant servers. It’s a dual-port 10/25GbE adapter based on the Mellanox (NVIDIA) ConnectX-6 Lx MCX6314 controller, delivering high throughput, low latency, and advanced offload capabilities for modern data center workloads.
Why buyers pick P42041-B21 (plain English)
High-performance 10/25Gb networking Supports both 10GbE and 25GbE, enabling flexible bandwidth upgrades without hardware replacement.
Low-latency Mellanox silicon Ideal for performance-sensitive workloads such as virtualization, storage, and container platforms.
Dual-port design Enables redundancy, link aggregation, or traffic segmentation across two network links.
Data-center ready features Well-suited for software-defined networking, storage traffic, and high-throughput east-west traffic.
HPE-qualified reliability Validated firmware and drivers ensure compatibility and long-term support in ProLiant servers.
Supported media SFP28 DAC cables or optical transceivers
Platform HPE ProLiant servers
Use case Virtualization, HCI, storage networking, and high-performance data center workloads.
Where it fits (and when to choose something else)
Perfect for:
ProLiant servers needing low-latency networking
Virtualized and containerized environments
Storage traffic (vSAN, iSCSI, NVMe-oF)
10Gb → 25Gb Ethernet upgrades
Choose something else if:
You only need basic networking → 10Gb SFP+ adapters
You need copper Ethernet → RJ-45 NICs
You need 40Gb or 100Gb → higher-speed Mellanox adapters
TL;DR
P42041-B21 is HPE’s dual-port 10/25GbE Mellanox ConnectX-6 Lx network adapter: a high-performance, low-latency NIC built for modern ProLiant server workloads.
Key specifications
Feature
Specification
Device Type
Network adapter
Part Number
P42041-B21
Manufacturer
Mellanox (NVIDIA)
Form Factor
OCP 3.0 (Plug-in mezzanine card)
Interface (Bus) Type
PCI Express 4.0 x8
Ports
Dual SFP28 ports (2x)
Data Transfer Rate
Supports 10 Gigabit Ethernet and 25 Gigabit Ethernet
HPE ProLiant Gen10 Plus and some Gen11 servers that support OCP 3.0
Features and benefits
High-performance networking:The adapter's dual SFP28 ports deliver high throughput for applications that demand significant bandwidth.
Reduced CPU offload:Support for Remote Direct Memory Access (RDMA) over Converged Ethernet (RoCE) offloads network tasks from the server's CPU, improving overall system efficiency.
Optimized for virtualization:Features like Single Root I/O Virtualization (SR-IOV) and Network Partitioning (NPAR) improve performance and efficiency in virtualized environments.
Enhanced security:The firmware is authenticated using a hardware root-of-trust, helping to protect against unauthorized modifications.
OCP 3.0 form factor:The standardized OCP 3.0 design allows for streamlined installation and maintenance in compatible HPE server models.
