HPE 656596-B21

Overview

The HPE 656596-B21 is a 10-gigabit Ethernet adapter designed to enhance server networking with two independent BASE-T ports capable of running at 10Gb or 1Gb speeds. It installs in a PCIe Gen2 x8 slot and supports copper connections over standard CAT 6A cables up to 100 meters, making it a practical choice for rack and edge environments that want to avoid fiber cabling. This adapter offloads critical network tasks from the CPU, improving overall server efficiency and supporting virtualization workloads with features tailored for VMware and Microsoft environments.

Key features

• Two independent BASE-T ports that support both 10Gb and 1Gb operation, allowing flexible network upgrades without changing existing cabling.
• PCIe Gen2 x8 interface provides sufficient bandwidth to handle high-speed data transfers without bottlenecks.
• Compatibility with standard CAT 6A cables up to 100 meters reduces infrastructure costs by eliminating the need for fiber optics in many setups.
• Stateless offloads such as TCP segmentation and checksum calculations reduce CPU load, freeing resources for application processing or virtual machine density.
• Virtualization support with VMware NetQueue and Microsoft VMQ distributes network processing across multiple CPU cores, maintaining low latency during heavy I/O operations.
• Built-in TCP Offload Engine and MSI/MSI-X interrupt balancing help sustain line-rate throughput while keeping server utilization efficient.
• Standup form factor designed to fit seamlessly into HPE ProLiant servers, simplifying upgrades and replacements.

Key specs

• Network ports: 2 x BASE-T
• Speed: 10Gb and 1Gb per port
• Interface: PCIe Gen2 x8
• Cabling: Supports CAT 6A copper cables up to 100 meters
• Controller: 57810S
• Offload features: TCP segmentation, checksum offload, TCP Offload Engine
• Virtualization: VMware NetQueue, Microsoft VMQ
• Form factor: Standup, compatible with HPE ProLiant servers

Connectivity and compatibility

This adapter is designed to integrate smoothly with existing network infrastructure using standard CAT 6A cables, which are common in data centers and enterprise environments. Its two BASE-T ports provide flexible connectivity options, supporting both 1Gb and 10Gb speeds to match current network equipment and future upgrades. The PCIe Gen2 x8 interface ensures that the adapter can communicate efficiently with the host server, making it suitable for a wide range of HPE ProLiant systems.

Performance and reliability

By offloading network processing tasks such as TCP segmentation and checksum calculations, the adapter reduces CPU overhead, which is critical for servers handling demanding workloads or multiple virtual machines. The inclusion of virtualization enhancements like VMware NetQueue and Microsoft VMQ helps maintain low latency and balanced CPU usage during heavy network traffic. These features make the adapter a strong choice for database servers, web front ends, and backup targets that require consistent high throughput and reliability.

Ideal uses and environments

This Ethernet adapter fits well in data centers and enterprise environments aiming to consolidate network traffic or migrate to 10Gb Ethernet without replacing existing cabling. It is particularly suited for IT teams managing HPE ProLiant servers who need a straightforward upgrade path to higher bandwidth. The adapter supports virtualization-heavy workloads and large-scale data transfers, making it a practical option for businesses that require efficient network performance and scalability.

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