HPE InfiniBand XDR PCIe Gen 6 Multi Host/Socket Direct Auxiliary Card — P81264-H21

The HPE P81264-H21 is an InfiniBand XDR PCIe Gen 6 x16 multi-host / socket-direct auxiliary card bundled with a 250mm MCIO cable kit. Designed for high-density GPU and compute node configurations, it enables socket-direct or multi-host InfiniBand XDR connectivity without consuming a standard PCIe slot, reducing fabric latency and improving GPU-to-fabric bandwidth in HPE AI infrastructure.

Key Features

• InfiniBand XDR PCIe Gen 6 x16 auxiliary card for multi-host and socket-direct deployments
• 250mm MCIO cable kit included for internal server connectivity to host PCIe Gen 6 fabric
• Socket-direct architecture minimizes hop latency between GPU and InfiniBand fabric
• Designed for dense AI and HPC compute node configurations requiring high fabric density

Product Specifications

• Part Number: P81264-H21
• Manufacturer: HPE
• Type: InfiniBand XDR Auxiliary Card (Multi Host/Socket Direct)
• Host Interface: PCIe Gen 6 x16
• Cable Kit: 250mm MCIO cable included
• Form Factor: Auxiliary card (internal connectivity)

Interface Specifications

• Host Interface: PCI Express Gen 6 x16 via MCIO internal cable
• Fabric Protocol: InfiniBand XDR
• Connectivity: Multi-host or socket-direct internal auxiliary card attachment
• Cable: 250mm MCIO cable for server-internal PCIe Gen 6 routing

Network & Protocol Specifications

• InfiniBand Standard: XDR (Extended Data Rate)
• Topology: Multi-host / socket-direct — multiple hosts or CPU sockets sharing fabric connection
• RDMA: Full InfiniBand RDMA support for MPI, NCCL, and storage fabric workloads
• Latency: Reduced fabric hop latency via socket-direct attachment vs. PCIe riser routing

Use Cases

• Dense AI GPU server configurations requiring socket-direct InfiniBand XDR connectivity
• Multi-host InfiniBand fabric sharing across multiple hosts or sockets in HPE AI platforms
• HPC compute nodes requiring internal PCIe Gen 6 InfiniBand routing via MCIO cable
• Reducing PCIe switch hop latency in GPU-dense HPE ProLiant Gen11 AI servers

Compatibility

• HPE ProLiant Gen11 AI and HPC compute nodes with PCIe Gen 6 x16 MCIO connectivity
• Compatible with InfiniBand XDR switch fabric infrastructure
• Requires MCIO-capable PCIe Gen 6 host platform for auxiliary card attachment

Frequently Asked Questions

What is a socket-direct InfiniBand configuration?

Socket-direct connects the InfiniBand HCA directly to a CPU socket's PCIe lanes via an internal cable, bypassing the PCIe switch. This reduces latency for GPU-to-fabric communication and improves MPI and NCCL collective performance in multi-socket AI servers.

What is an MCIO cable and why is it included?

MCIO (Mini Cool Edge IO) is a compact, high-speed internal PCIe cable connector used in dense server designs. The 250mm MCIO cable connects the auxiliary card to the host PCIe Gen 6 interface internally, enabling low-latency socket-direct InfiniBand connectivity without an external PCIe riser.

Is P81264-H21 a standalone network adapter?

No — P81264-H21 is an auxiliary card designed to work with a primary InfiniBand XDR HCA. It enables multi-host or socket-direct fabric attachment and is not a standalone network adapter with external ports.

The HPE P81264-H21 InfiniBand XDR PCIe Gen 6 multi-host auxiliary card enables low-latency socket-direct fabric connectivity for HPE AI and HPC dense compute deployments. Order today — in stock at the best price.